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so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so once again , our slope here is a constant positive line . let me be careful here because at this point , our slope wo n't really be defined , because our slope , you could draw multiple tangent lines at this little pointy point . so let me just draw a circle right over there .
why ca n't the slope be defined at this point ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
our slope is a constant positive value . so once again , our slope here is a constant positive line . let me be careful here because at this point , our slope wo n't really be defined , because our slope , you could draw multiple tangent lines at this little pointy point .
so if a line on a function is constant ( straight ) then is the derivative going to always be a straight horizontal line as well ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but then when we go over here , even though the value of our function has gone down , we still have a constant positive slope . in fact , the slope of this line looks identical to the slope of this line . let me do that in a different color .
why do the beginning of the pink line and the end of the orange line not end in open circles ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and then we look at this point right over here . so right at this point , our slope is going to be undefined . there 's no way that you could find the slope over -- or this point of discontinuity .
should n't the derivative be undefined at those spots , because we only know the limit from one side ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and so when you look at the derivative , the slope is still a positive value . but as we get larger and larger x 's up to this point , the slope is getting less and less positive , all the way to 0 . and then the slope is getting more and more negative .
5 , why does sal put the point on the x axis ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
here the slope seems constant . our slope is a constant positive value . so once again , our slope here is a constant positive line .
why is the y value zero ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and then we look at this point right over here . so right at this point , our slope is going to be undefined . there 's no way that you could find the slope over -- or this point of discontinuity .
why the last jump of the derivate ( ) is a defined point and not undefined ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope .
how does one know what specific points to draw the derivative through ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but the whole point of this video is to give you an intuition for thinking about what the slope of this function might look like at any point . and by doing so , we have essentially drawn the derivative over that interval .
in other words , how is the y-intercept of the derivative determined ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here .
is there a difference between f ( x ) lines that in end in closed circles vis-a-vis lines that end in open circles ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so once again , our slope here is a constant positive line . let me be careful here because at this point , our slope wo n't really be defined , because our slope , you could draw multiple tangent lines at this little pointy point . so let me just draw a circle right over there .
sal said the derivative of the point does n't exist , why ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but the whole point of this video is to give you an intuition for thinking about what the slope of this function might look like at any point . and by doing so , we have essentially drawn the derivative over that interval .
if derivatives are functions themselves , i 'm assuming it 's possible to take the derivative of a derivative ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but the whole point of this video is to give you an intuition for thinking about what the slope of this function might look like at any point . and by doing so , we have essentially drawn the derivative over that interval .
how does one determine a derivative exists ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope .
for a derivative to exist the function has to be continuous , right ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so we could say -- let me make it clear what interval i 'm talking about -- the slope over this interval is 0 . and then finally , in this last section -- let me do this in orange -- the slope becomes negative . but it 's a constant negative .
in the orange line ( the last section of the derivative graph ) have an open or closed hole ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but the whole point of this video is to give you an intuition for thinking about what the slope of this function might look like at any point . and by doing so , we have essentially drawn the derivative over that interval .
can the graph of the derivative be drawn in any number of ways , since different graphs often have the same interpretation or is there a set graph that a derivative of a function has to be ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
let me be careful here because at this point , our slope wo n't really be defined , because our slope , you could draw multiple tangent lines at this little pointy point . so let me just draw a circle right over there . but then as we get right over here , the slope seems to be positive .
why does n't sal shade the circle ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
now let 's think about as we get to this point . here the slope seems constant . our slope is a constant positive value .
so the prime graph reflects only the slope ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and it seems actually a little bit more negative than these were positive . so i would draw it right over there . so it 's a weird looking function . but the whole point of this video is to give you an intuition for thinking about what the slope of this function might look like at any point . and by doing so , we have ...
if i were told to sketch the graph of an even function f ( x ) which has a derivative at every point , how would it look like ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
notice here , for example , the slope is still positive . and so when you look at the derivative , the slope is still a positive value . but as we get larger and larger x 's up to this point , the slope is getting less and less positive , all the way to 0 .
how do we know that for a fact that wherever the turning point is , that is the same value of the x-intercept for the derivative ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and once again , it 's undefined here at this point of discontinuity . so the slope will look something like that . and then we go up here .
can you consider then , that since the derivative of the slope is measuring the change in y with respect to x , that graphing the derivative of a function , that is measuring something like say , speed , would resulting in the graphing of the change in velocity over time when compared to the graph of the function ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
here the slope seems constant . our slope is a constant positive value . so once again , our slope here is a constant positive line .
how is the slope , the way it is drawn , positive when sal is talking exactly ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but then when we go over here , even though the value of our function has gone down , we still have a constant positive slope . in fact , the slope of this line looks identical to the slope of this line . let me do that in a different color .
could someone explain why sal drew the lines on different levels and not one continuous line ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and we just said we have a constant positive slope . so let 's say it looks something like that over this interval . and then we look at this point right over here .
, what i mean to say is that why are some lines above the x-axis like the yellow and red lines while the blue one is on the x-axis ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here .
at what values of x is f ( x ) continuous but not differentiable ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but then when we go over here , even though the value of our function has gone down , we still have a constant positive slope . in fact , the slope of this line looks identical to the slope of this line . let me do that in a different color .
in the example , was there a reason behind sal sketching the line at that specific point on the y-axis ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and then we look at this point right over here . so right at this point , our slope is going to be undefined . there 's no way that you could find the slope over -- or this point of discontinuity .
so , my question is , how can you take the slope of an undefined slope ( whether because of discontinuity or not ) and thus taking the derivative of a function where that function is undefined ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope .
the derivative of the parabolic portion of the function is explained/represented as a straight line , whereas in the video , `` figuring out which function is the derivative '' , what appears to be a similar figure for f ( x ) has a derivative line that is not straight ( rather , sigmoidal ) - ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and then we go up here . the value of the function goes up , but now the function is flat . so the slope over that interval is 0 .
in first interval there is sine function then why the derivative of that function is straight line ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so let 's say it looks something like that over this interval . and then we look at this point right over here . so right at this point , our slope is going to be undefined .
yet a unique limit for that point exists , so it should also exist a derivative right ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but then when we go over here , even though the value of our function has gone down , we still have a constant positive slope . in fact , the slope of this line looks identical to the slope of this line . let me do that in a different color .
is the derivative of that slope the stangent line stretched from one point to another on a slope ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here .
why is the derivative of y=x computed as x=1 , should n't it be y=-x to make it according to the slope signs ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
and it seems actually a little bit more negative than these were positive . so i would draw it right over there . so it 's a weird looking function .
if you took that ( red ) segment as an interval alone and evaluated it , would n't the f ' ( x ) of its left endpoint still be defined because the limit would only include evaluation from the positive side ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
but let 's say that , so let 's see , here the slope is quite positive . so let 's say the slope is right over here . and then it gets less and less and less positive .
would you say that the drawing of the slope/derivative on the second graph must be between [ -1,1 ] because the slope must always be a fraction , therefore between these two numbers ?
so i 've got this crazy discontinuous function here , which we 'll call f of x . and my goal is to try to draw its derivative right over here . so what i 'm going to need to think about is the slope of the tangent line , or the slope at each point in this curve , and then try my best to draw that slope . so let 's try ...
so it gets less and less and less positive . notice here , for example , the slope is still positive . and so when you look at the derivative , the slope is still a positive value . but as we get larger and larger x 's up to this point , the slope is getting less and less positive , all the way to 0 .
what would be the derivative of an infinitely changing slope ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
let 's let x be equal to the degree measure of my brother 's pie or your little brother 's pie . so this is degree measure of brother 's pie . and then what would the amount of pie you eat be ? well , it says you eat twice what your little brother eats .
where did the idea come from that these 3 slices would consume the entire remains of the pie ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
and then we are left with 3x equaling 180 degrees minus 30 degrees is equal to 150 degrees . and now we can just divide both sides by 3 , and we 're left with x equaling 150 divided by 3 is 50 degrees . x is equal to 50 degrees . now , we have to be careful .
could n't you just do 180-30=150 , then divide 150 by 3 which equals 50 , and then multiply 50 times 2 to get 100 ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
so that is 2x . x is the measure of this angle , and then 2x is a measure of that angle . so you see that 30 degrees plus x plus 2x , or x plus 2x plus 30 degrees , is going to be equal to 180 degrees .
what is the measure of the larger angle in degrees ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
let 's let x be equal to the degree measure of my brother 's pie or your little brother 's pie . so this is degree measure of brother 's pie . and then what would the amount of pie you eat be ? well , it says you eat twice what your little brother eats .
where did the idea come from that these 3 slices would consume the entire remains of the pie ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
let 's let x be equal to the degree measure of my brother 's pie or your little brother 's pie . so this is degree measure of brother 's pie . and then what would the amount of pie you eat be ? well , it says you eat twice what your little brother eats .
does your family have to eat the whole pie ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
so if we had a whole pie -- so if we started here , and we had a whole pie , we went all the way around , that would be 360 degrees . but we only have a half pie . so we only have 180 degrees and let me do that in a color you 're more likely to see .
how many slices did sam cut the pie into ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
so that is 2x . x is the measure of this angle , and then 2x is a measure of that angle . so you see that 30 degrees plus x plus 2x , or x plus 2x plus 30 degrees , is going to be equal to 180 degrees .
what is the complement of an angle ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
so that is 2x . x is the measure of this angle , and then 2x is a measure of that angle . so you see that 30 degrees plus x plus 2x , or x plus 2x plus 30 degrees , is going to be equal to 180 degrees .
and what is the supplement of an angle ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ?
how many degrees is the smaller slice ?
there is a half an apple pie left . you want to eat twice what your little brother eats , but you also need to save a slice for your mom . you can cut her a slice that is 30 degrees . what is the measure of your piece of the pie in degrees ? so to tackle this , we just have to remember a few things . we have to remembe...
so that is 2x . x is the measure of this angle , and then 2x is a measure of that angle . so you see that 30 degrees plus x plus 2x , or x plus 2x plus 30 degrees , is going to be equal to 180 degrees .
what is the measure of abc ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
the athenian navy is getting more and more powerful . and once again , things culminate , and now this is the beginning of the actual peloponnesian war , the thing that people are referring to when they talk about the peloponnesian war . in 431 bce , the king of sparta is convinced or is , i guess you could say he is i...
why are these wars ( greco-persian , peloponnesian ) so important that they are taught to children across europe and in other societies of european origin ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
and so this is the attack at syracuse . attack at syracuse , the failed attempt of the athenians to get syracuse , to get syracuse . and this is a two-year period of time , because once again , this is no joke to send your navy and to try to get at syracuse .
what was the point of syracuse ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
and so this is the attack at syracuse . attack at syracuse , the failed attempt of the athenians to get syracuse , to get syracuse . and this is a two-year period of time , because once again , this is no joke to send your navy and to try to get at syracuse .
did syracuse use navel or ground or both to fend off athens ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
attica 's something you 'll hear a lot about . it is this region right over here , this little out-jutting of land , that athens is on . and this first phase of the peloponnesian war is called the archidamian war , named for the king of sparta who somewhat reluctantly decides to invade attica .
when rome took over athens the romans took the statue of athena from the parthenon right ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
but it 's not a great victory because as you can imagine , you have towns that have been destroyed , large parts of greece have been weakened , and it leaves the whole area open to attack from others . and as we will see in the next century , in the 4th century , we have phillip of macedon , or macedon depending on how...
so what 's the difference between `` macedon '' and `` macedonia '' ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
the third phase is often called the ionian war . ionian war . ionia is this region that 's now in modern day , off the coast of modern-day turkey .
which city-states were neutral during the peloponnesian war ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
and we even saw it in the last video , you have an earthquake in sparta , potentially right around the same time that sparta was planning an invasion of athens , leaving the spartans vulnerable . there 's a helot uprising , these spartan slaves . the athenians send hoplites to apparently help the spartans but the spart...
did the helot uprising continue thrueout the peloponnesian war ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
the third phase is often called the ionian war . ionian war . ionia is this region that 's now in modern day , off the coast of modern-day turkey .
what happened after the peloponnesian war ?
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies . sp...
as we 've already seen , the 5th century bce starts off with athens and sparta and various greek city-states fighting on the same side against the persian invaders . but as we saw in the last video , as soon as the persians are dealt with , tensions start to rise between athens and sparta and their various allies .
do we know that from the greek historian sources as well ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
but it is certainly not a normal part of aging . so , dementia , in very general terms , is something we use to describe when someone has troubles learning , remembering , and communicating . but where does alzheimer 's disease fit into this ? well , alzheimer 's disease is a type of dementia .
can someone be diagnosed with alzheimer 's , or do you have to guess , like schizophrenia ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
for example somebody with dementia might have troubles with speaking or writing coherently , or understanding what was spoken or written . they also might have trouble recognizing their surroundings , especially when those surroundings should normally be very familiar to them . planning and performing tasks that requir...
also , are the symptoms universal , or do they vary from patient to patient ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
when problems remembering or problems with your thinking skills in general become so severe and so common that they actually interfere with your daily life , it might be diagnosed as dementia . dementia , though , is not a specific disease . what do i mean by that ?
would chronic traumatic encephalopathy be considered a form of dementia ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
when problems remembering or problems with your thinking skills in general become so severe and so common that they actually interfere with your daily life , it might be diagnosed as dementia . dementia , though , is not a specific disease . what do i mean by that ?
can dementia happen in younger people ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
unfortunately , though , the main type of cells that alzheimer 's disease targets and affects are these precious neurons . and depending on where the affected neurons live in your brain , different functions of your brain can be affected . for example , if nerve cells in this area of your cerebrum are affected , you mi...
do all people have the same symptoms or are they different per person ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
but where does alzheimer 's disease fit into this ? well , alzheimer 's disease is a type of dementia . specifically , it 's what 's known as a neuro degenerative disease , and it counts for about 60 to 80 % of all cases of dementia , affecting about five million people .
are infectious agents the other cause of dementia apart from alzheimer ?
let 's say you 're going to the grocery store , but you realize you left your keys in your room . you go up to get them and then walk into the room and look around for a second , and realize you completely forgot why you even came here in the first place . we all know how frustrating this can be , right ? but this sce...
and to make matters worse , many times , patients are n't even aware that they 're experiencing any troubles or any sort of cognitive deficiencies at all . now , dementia is most common in the elderly , especially after age 65 . but it is certainly not a normal part of aging .
do you have any ideas on keeping an elderly person 's mind active to prevent the worsening of dementia ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and before i show you how to do that , let me give you one more piece of terminology . the longest side of a right triangle is the side opposite the 90 degree angle -- or opposite the right angle . so in this case it is this side right here .
is the hypotenuse the longest side of the right triangle , or the side opposite of the right angle ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so that 's what b squared is , and now we want to take the principal root , or the positive root , of both sides . and you get b is equal to the square root , the principal root , of 108 . now let 's see if we can simplify this a little bit .
if you square root the whole equation , should n't it be a+b=c ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and in this circumstance we 're solving for the hypotenuse . and we know that because this side over here , it is the side opposite the right angle . if we look at the pythagorean theorem , this is c. this is the longest side .
can you find the height of the triangle when you know the side lengths ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
what is this ? 2 times 2 is 4 . 4 times 9 , this is 36 .
other than ( 3,4,5 ) , which sets of whole numbers are solutions to the equation a^2+b^2=c^2 ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so let 's say that that is my triangle , and this is the 90 degree angle right there . and i think you know how to do this already . you go right what it opens into .
how do you know when to simplify and when not to ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so this is going to be 108 . so that 's what b squared is , and now we want to take the principal root , or the positive root , of both sides . and you get b is equal to the square root , the principal root , of 108 . now let 's see if we can simplify this a little bit .
what is a principle root ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
let 's say a is equal to 6 . and then we say b -- this colored b -- is equal to question mark . and now we can apply the pythagorean theorem .
how do you know which leg is `` a '' and the other is `` b '' ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
let me tell you what the pythagorean theorem is . so if we have a triangle , and the triangle has to be a right triangle , which means that one of the three angles in the triangle have to be 90 degrees . and you specify that it 's 90 degrees by drawing that little box right there .
so the square in the middle of the triangle multiplies the outer numbers ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
you go opposite the right angle . the longest side , the hypotenuse , is right there . so if we think about the pythagorean theorem -- that a squared plus b squared is equal to c squared -- 12 you could view as c. this is the hypotenuse .
is the hypotenuse the longest side of any triangle or just the longest side of a right triangle ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
now let 's see if we can simplify this a little bit . the square root of 108 . and what we could do is we could take the prime factorization of 108 and see how we can simplify this radical .
is there a negative square root ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and then we say b -- this colored b -- is equal to question mark . and now we can apply the pythagorean theorem . a squared , which is 6 squared , plus the unknown b squared is equal to the hypotenuse squared -- is equal to c squared .
why does the pythagorean theorem not work on other triangles like obtuse or acute ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
let 's say that our triangle looks like this . and that is our right angle . let 's say this side over here has length 12 , and let 's say that this side over here has length 6 .
is there any way to solve for the missing angle using pythagoras theorem ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and the way to figure out where that right triangle is , and kind of it opens into that longest side . that longest side is called the hypotenuse . and it 's good to know , because we 'll keep referring to it .
is there a way to make the hypotenuse the same as another side ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
now let 's see if we can simplify this a little bit . the square root of 108 . and what we could do is we could take the prime factorization of 108 and see how we can simplify this radical .
why ca n't we just do the square root of 108 even if it ends up a decimal ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and the way to figure out where that right triangle is , and kind of it opens into that longest side . that longest side is called the hypotenuse . and it 's good to know , because we 'll keep referring to it .
i learnt that c is the hypotenuse , however , how do you know which side is a and which is b ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and then we say b -- this colored b -- is equal to question mark . and now we can apply the pythagorean theorem . a squared , which is 6 squared , plus the unknown b squared is equal to the hypotenuse squared -- is equal to c squared .
is there a type of pythagorean theorem for other triangles ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
now let 's see if we can simplify this a little bit . the square root of 108 . and what we could do is we could take the prime factorization of 108 and see how we can simplify this radical .
at the end why would you put under a square root/ radical sign ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and then we say b -- this colored b -- is equal to question mark . and now we can apply the pythagorean theorem . a squared , which is 6 squared , plus the unknown b squared is equal to the hypotenuse squared -- is equal to c squared .
what does pythagorean theorem actually means ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
that is 16 . and 3 squared is the same thing as 3 times 3 . so that is 9 .
is 3,4,5 and its multiples the only numbers that make the pythagorean theorem work ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
or , we could call it a right angle . and a triangle that has a right angle in it is called a right triangle . so this is called a right triangle . now , with the pythagorean theorem , if we know two sides of a right triangle we can always figure out the third side .
why does it have to be a right triangle ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
let 's say that our triangle looks like this . and that is our right angle . let 's say this side over here has length 12 , and let 's say that this side over here has length 6 .
why would n't the pythagorean theorem work on non-right angle triangles ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and it 's good to know , because we 'll keep referring to it . and just so we always are good at identifying the hypotenuse , let me draw a couple of more right triangles . so let 's say i have a triangle that looks like that .
does the theorem work for non-right triangles ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
4 times 9 , this is 36 . so this is the square root of 36 times the square root of 3 . the principal root of 36 is 6 .
why does sal write the square root of the last 3 ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
or , we could call it a right angle . and a triangle that has a right angle in it is called a right triangle . so this is called a right triangle . now , with the pythagorean theorem , if we know two sides of a right triangle we can always figure out the third side .
so only right triangle works ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
we have the right angle here . you go opposite the right angle . the longest side , the hypotenuse , is right there .
if the triangle edge opposite the right angle is called the hypotenuse , do the other two sides have their own names as well ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and before i show you how to do that , let me give you one more piece of terminology . the longest side of a right triangle is the side opposite the 90 degree angle -- or opposite the right angle . so in this case it is this side right here .
is hypotenuse the opposite of the 90 degree angle of a triangle or the opposite of any angle that we want to take ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so this is called a right triangle . now , with the pythagorean theorem , if we know two sides of a right triangle we can always figure out the third side . and before i show you how to do that , let me give you one more piece of terminology .
is there a way to apply the pythagorean theorem to find the other two sides if you know only one side ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and the way to figure out where that right triangle is , and kind of it opens into that longest side . that longest side is called the hypotenuse . and it 's good to know , because we 'll keep referring to it .
why is the hypotenuse the longest side ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry .
how many laws and theorems are there in math ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
we have the right angle here . you go opposite the right angle . the longest side , the hypotenuse , is right there .
if the triangle edge opposite the right angle is called the hypotenuse , do the other two sides have their own names as well ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and before i show you how to do that , let me give you one more piece of terminology . the longest side of a right triangle is the side opposite the 90 degree angle -- or opposite the right angle . so in this case it is this side right here .
if it says the hypotenuse is the side opposite the right angle does that mean that pythagoras ' theorem is only used to figure out the hypotenuse ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
what is this ? 2 times 2 is 4 . 4 times 9 , this is 36 .
if a^2 + b^2 = c^2 ; does that mean a + b = c ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
what is this ? 2 times 2 is 4 . 4 times 9 , this is 36 .
if a^2 + b^2 = c^2 , does n't that mean you can make it more simple and do a + b = c ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so 25 is equal to c squared . and we could take the positive square root of both sides . i guess , just if you look at it mathematically , it could be negative 5 as well .
how could you solve for the square root of pi ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
the longest side , the hypotenuse , is right there . so if we think about the pythagorean theorem -- that a squared plus b squared is equal to c squared -- 12 you could view as c. this is the hypotenuse . the c squared is the hypotenuse squared . so you could say 12 is equal to c. and then we could say that these sides...
could n't we just do a + b = c ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
or , we could call it a right angle . and a triangle that has a right angle in it is called a right triangle . so this is called a right triangle . now , with the pythagorean theorem , if we know two sides of a right triangle we can always figure out the third side . and before i show you how to do that , let me give y...
can a triangle have two right angles ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
so let 's say i have a triangle that looks like that . and i were to tell you that this angle right here is 90 degrees . in this situation this is the hypotenuse , because it is opposite the 90 degree angle .
90 + 90 is 180 , and the other angle would have 0 which is no angle ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and then we say b -- this colored b -- is equal to question mark . and now we can apply the pythagorean theorem . a squared , which is 6 squared , plus the unknown b squared is equal to the hypotenuse squared -- is equal to c squared .
can the pythagorean theorem be applyed to polygons or other shapes ?
in this video we 're going to get introduced to the pythagorean theorem , which is fun on its own . but you 'll see as you learn more and more mathematics it 's one of those cornerstone theorems of really all of math . it 's useful in geometry , it 's kind of the backbone of trigonometry . you 're also going to use it ...
and the way to figure out where that right triangle is , and kind of it opens into that longest side . that longest side is called the hypotenuse . and it 's good to know , because we 'll keep referring to it .
why is the longer line called the hypotenuse ?