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a line passes through the points negative 3 , 6 and 6 , 0 . find the equation of this line in point slope form , slope intercept form , standard form . and the way to think about these , these are just three different ways of writing the same equation . so if you give me one of them , we can manipulate it to get any of...
so if you give me one of them , we can manipulate it to get any of the other ones . but just so you know what these are , point slope form , let 's say the point x1 , y1 are , let 's say that that is a point on the line . and when someone puts this little subscript here , so if they just write an x , that means we 're ...
was n't sal supposed to write y1-y2=m ( x1-x2 ) ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
well , just think about this a little bit . if i square something , and if it 's greater than 1 -- so that means that either b is less than negative 1 , because if it was negative 1 , if you squared it , you would get 1 . if it was greater than negative 1 , or just directly greater than negative 1 , if it was negative ...
when you divide a out do you always replace the empty side with 1 ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
well , just think about this a little bit . if i square something , and if it 's greater than 1 -- so that means that either b is less than negative 1 , because if it was negative 1 , if you squared it , you would get 1 . if it was greater than negative 1 , or just directly greater than negative 1 , if it was negative ...
why did sal get 1 when he divided a by a ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
well , just think about this a little bit . if i square something , and if it 's greater than 1 -- so that means that either b is less than negative 1 , because if it was negative 1 , if you squared it , you would get 1 . if it was greater than negative 1 , or just directly greater than negative 1 , if it was negative ...
when using 1 and -1 ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so a/b is going to be to the right of a times b . so we know that a/b , it has to be negative . it has to be the left of 0. a/b is going to be to the right of a times b .
what do we do if we do n't know for sure if b is negative or if it could be both ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
i 'm going to rewrite it . so b times a/b is going to negative . we know it 's negative .
since we know b is negative , why do n't we reverse the inequality when multiplying a/b * b ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so since we know b is less than 0 , we can take this out of the picture . and if the absolute value of b is greater than 1 , and b is less than 0 , then we know that b has to be less than negative 1 . so wherever negative 1 is , b is going to be less than that .
would n't the absolute value of 'b ' also have to be greater than 'a ' as the fraction -a/b is less than the multiplication product - ( a*b ) ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
and she says , all right . so you have two integers , integer a and integer b . and she tells you that integer a is greater than 0 , and integer b is less than 0 .
so does an inequality always flips if you divide or multiply both side by a negative integer ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
and she says , all right . so you have two integers , integer a and integer b . and she tells you that integer a is greater than 0 , and integer b is less than 0 .
how about if you add and subtract a negative integer to both sides ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
i 'm going to rewrite it . so b times a/b is going to negative . we know it 's negative .
ca n't we also say that `` b '' is larger than `` a '' because of the inequality a/b > ab ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
but let 's actually manipulate , algebraically manipulate this inequality here . we could multiply both sides times b . so let 's do that .
does this mean you cant multiply both sides of an inequality by a variable unless you knows it 's sign ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
let 's multiply both sides times b. b is less than the 0 . so if you 're multiplying both sides of an inequality by something less than 0 , it swaps the inequality . that 's why i got rid of it .
is there a video reference that would discuss why multiplying both side of an inequality with something less than zero would swap the inequality ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
i 'm going to rewrite it . so b times a/b is going to negative . we know it 's negative .
why does sal put `` b '' in these lines ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
let 's multiply both sides times b. b is less than the 0 . so if you 're multiplying both sides of an inequality by something less than 0 , it swaps the inequality . that 's why i got rid of it .
what applications use reasoning through inequality expressions ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
i 'm going to rewrite it . so b times a/b is going to negative . we know it 's negative .
how is a/b greater that a*b ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
i 'm going to rewrite it . so b times a/b is going to negative . we know it 's negative .
how did sal change b^2 into absolute b ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so since we know b is less than 0 , we can take this out of the picture . and if the absolute value of b is greater than 1 , and b is less than 0 , then we know that b has to be less than negative 1 . so wherever negative 1 is , b is going to be less than that .
i do n't understand how b^2 > 1 turns out to be i b i > 1 ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
if it was greater than negative 1 , or just directly greater than negative 1 , if it was negative 0.99 , then when you square it , it would be something less than 1 . so that does n't work . so b has to be less than negative 1 or b has to be greater than 1 , because for the same exact logic .
is n't the distance from zero also called magnitude ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
or another way we could think about this , we could say , well , if 1 is less than b squared , that means that b -- let 's be careful here -- that means that the absolute value of b is going to be greater than 1 . so this means that the absolute value of b is greater than 1 . and you say , wait , sal , how did you get ...
the greater the magnitude the larger the absolute value of the number ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so since we know b is less than 0 , we can take this out of the picture . and if the absolute value of b is greater than 1 , and b is less than 0 , then we know that b has to be less than negative 1 . so wherever negative 1 is , b is going to be less than that .
so it 's like saying a > 0 ( but it ca n't be 1 if ( b ) is -1 ) and b < 0 ( but it ca n't be -1 if ( a ) is 1 ) whats the practical application is what i want to know ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
if it was exactly equal to 1 , if you squared it , this would be equal . if it was 0.5 , then squared it would be 0.25 , which would n't be greater than . so you know both of these things are true .
is there an example in reality where such a constraint would arise ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so since we know b is less than 0 , we can take this out of the picture . and if the absolute value of b is greater than 1 , and b is less than 0 , then we know that b has to be less than negative 1 . so wherever negative 1 is , b is going to be less than that .
in why b < -1 or b > 1 is equivalente to /b/ > 1 ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so let 's do that . let 's multiply both sides times b. b is less than the 0 . so if you 're multiplying both sides of an inequality by something less than 0 , it swaps the inequality .
why do we started to multiply by b 'b ' at 3.34 and than divide ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so b times a/b is going to negative . we know it 's negative . so it 's going to be less than ab times b .
okaaaay , how do we know the numerator is positive and where is negative a ?
you go for a job interview . and the first thing that your interviewer says is , look , you have great work experience . you seem like a nice young person . but what i really care about is your logical reasoning capabilities . so what she says is , just sit down . i 'm going to ask you a question about some math expres...
so let 's do that . let 's multiply both sides times b. b is less than the 0 . so if you 're multiplying both sides of an inequality by something less than 0 , it swaps the inequality .
in a / b > ab why did sal first multiply each side by b ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
so that gives me 37 . and then 3/18 plus 2/3 , to add them , i need to have the same denominator . and the least common multiple of 18 and 3 is 18 .
what happens if a fractions denominator is 0 would it then be impossible to add it or subtract it ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
so ... when adding the two fractions , 3/18 and 2/3 , why ca n't we do that trick where we multiply the 18 by the 3 to get 54 denominator ... and then multiply the 18 by the 2 and the 3 by the other 3 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 .
why is the `` missing '' sign a + and not a x like it would in something like `` 7y '' ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and the least common multiple of 18 and 3 is 18 . so let 's convert 2/3 to something over 18 . so 2/3 , if i want to write it as something over 18 , well , i multiplied the denominator by 6 , so i 'd also have to multiply the numerator by 6 .
why are you going to convert 2/3 into something over '18 ' if the lcm is 37 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
are there tricks to simplifying odd fractions ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
19 plus 19 would be 38 . so this is going to be 1 less than that . it 's going to be 37 .
what do we do if we reach the part 5+7+1/3+1/4 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and so this gives us , we still have our 37 , but the numerator is now 5 , and the denominator is now 6 . so we get 37 and 5/6 . and we 're done .
where did the 6 come in ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and so this gives us , we still have our 37 , but the numerator is now 5 , and the denominator is now 6 . so we get 37 and 5/6 . and we 're done .
so 3/4 +2/6 would be 5/24 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
are there any tricks to knowing if a fration is already in lowest terms ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
so why does n't 19 3/8 + 18 2/3 become 345/18 + 168/18 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
so we could do 19 plus 18 . and then we can add the fraction parts -- let me do this in green -- plus 3/18 plus 2/3 . now 19/18 , pretty straightforward .
how do i do 3 3/4 x 4 4/5 do i convert to an improper fraction ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add the 19 to the 18 .
is there an easier way to add mixed numbers ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add the 19 to the 18 .
how can we add mixed numbers ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
3 plus 12 is 15 , plus 15/18 . and so expressing this as a mixed number , i get 37 and 15/18 . and that 's the right number .
are there any shortcuts when subtracting mixed numbers ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
what is 4135/36 what is the answer ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and then 3/18 plus 2/3 , to add them , i need to have the same denominator . and the least common multiple of 18 and 3 is 18 . so let 's convert 2/3 to something over 18 .
what does common multiple mean ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and so this gives us , we still have our 37 , but the numerator is now 5 , and the denominator is now 6 . so we get 37 and 5/6 . and we 're done .
how do you subtract 0.6 from 2 5/9 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and so expressing this as a mixed number , i get 37 and 15/18 . and that 's the right number . but we can simplify it even more .
do you take from the hole number ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
we can simplify the 15/18 . both the numerator and the denominator are divisible by 3 . so let 's divide them both by 3 .
is there an easier way to figure out a common denominator than writing out the multiples of each denominator until you get one that 's the same ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
19 plus 19 would be 38 . so this is going to be 1 less than that . it 's going to be 37 .
what is 36 1/4 - 24 8/9 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
what is 4 3/5 - 2 1/3 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
3 plus 12 is 15 , plus 15/18 . and so expressing this as a mixed number , i get 37 and 15/18 . and that 's the right number .
can you show me how to subtract small mixed numbers by big mixed numbers ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
3 plus 12 is 15 , plus 15/18 . and so expressing this as a mixed number , i get 37 and 15/18 . and that 's the right number .
cant you divide 37 into a smaller number ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
so we get 37 and 5/6 . and we 're done .
( counting milliseconds ) will there be a eclipse ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts .
my problem is 8 1/9 + 13 1/2 , my question is how can i divide the 2 to become 9 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
how much tape is left on the roll ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
that 's going to be -- so i have 37 plus -- it 's going to be something over 18 -- plus something over 18 . 3 plus 12 is 15 , plus 15/18 . and so expressing this as a mixed number , i get 37 and 15/18 . and that 's the right number .
how is 37 + 15/18 = 37 * 15/18 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and then 3/18 plus 2/3 , to add them , i need to have the same denominator . and the least common multiple of 18 and 3 is 18 . so let 's convert 2/3 to something over 18 .
how you fine a common denominators for mixed numbers ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
are there any ways to do 13 1/4 - 8 3/18 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
so that gives me 37 . and then 3/18 plus 2/3 , to add them , i need to have the same denominator . and the least common multiple of 18 and 3 is 18 .
what if the denominator 's do not have common multiples like 1/3+3/10 ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
why was n't 18 3/18 simplified to 18 1/6 before starting the operation ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts .
how do you add 3 mixed numbers with unlike denominators ?
let 's add 19 and 3/18 to 18 and 2/3 . so i like to separate out the whole number parts from the fraction parts . so 19 and 3/18 is the same thing as 19 plus 3/18 . and to that , we are going to add 18 and 2/3 , which is the same thing as 18 plus 2/3 . now we can separately add the whole number parts . so we could add ...
and then 3/18 plus 2/3 , to add them , i need to have the same denominator . and the least common multiple of 18 and 3 is 18 . so let 's convert 2/3 to something over 18 .
how did you find the least common denominator of 18 and 3 ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
so this first one , this first one i could write this as log base 10 of 16 , remember if i do n't write the base you can assume it 's 10 , over log over log base 10 of c , and we 're going to be multiplying this by , now this is going to be , we can write this as , log base 10 of c , log base 10 of c over , over log ba...
why is base 10 the default for logarithms ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
now let 's try to , now let 's try to tackle this one over here . so i 've log base c of 16 , times log base two of c , alright . so this one , once again it might be nice to re-write these , each of these , as a rational expression dealing with log base 10 .
even though that is typical , would n't it been faster in that particular example , where 16 is an exponent of 2 , to use log_2 16/log_2 c *log_2 c ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
log of b over log of four , which of course is just going to be log of b over log of four , i just multiplied it by one , and so we can go in the other direction now , using this little tool we established at the beginning of the video . this is the same thing as log base four of b , log base four of b . so we have a p...
should n't the 1/log_a b = log_b a be a logarithm property ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
and i 'll give you an even further hint . when i 'm talking about change of base , i 'm saying that if i have the log base , and i 'll color code it , log base a of b , log base a of b , this is going to be equal to log of b , log of b over log of a , over log of a . now you might be saying wait , wait , wait , we wrot...
what is the difference between log ( m/n ) and log m/log n ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
now let 's try to , now let 's try to tackle this one over here . so i 've log base c of 16 , times log base two of c , alright . so this one , once again it might be nice to re-write these , each of these , as a rational expression dealing with log base 10 .
according to : log_c ( 16 ) * log_2 ( c ) = log_2 ( 16 ) = 4 instead of all the calcul shown in the video , could we do something like : log_c ( 16 ) * log_2 ( c ) = log_2c ( 16c ) and because of this property : log_b ( b^c ) = 1 , can we simply the c 's of log_2c ( 16c ) ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
so this first one , this first one i could write this as log base 10 of 16 , remember if i do n't write the base you can assume it 's 10 , over log over log base 10 of c , and we 're going to be multiplying this by , now this is going to be , we can write this as , log base 10 of c , log base 10 of c over , over log ba...
can the log base be something other than base 10 ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
now let 's try to , now let 's try to tackle this one over here . so i 've log base c of 16 , times log base two of c , alright . so this one , once again it might be nice to re-write these , each of these , as a rational expression dealing with log base 10 .
so , from the 2nd problem can we conclude that ( log ( base a of b ) ) * ( log ( base c of a ) ) = ( log ( base c of b ) ) ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way .
when sal is simplifying log16/log2 , why would it not be log8 ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
so we have a pretty neat result that actually came out here , we did n't prove it for any values , although we have a pretty general b here . if i take the , if i take the reciprocal of a logarithmic expression , i essentially have swapped the bases . this is log base b , what exponent do i have to raise b to to get to...
or from what he did , can you take log16/log2 , cancel the logs and divide 16 by 2 , which would give you 8 ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
now let 's try to , now let 's try to tackle this one over here . so i 've log base c of 16 , times log base two of c , alright . so this one , once again it might be nice to re-write these , each of these , as a rational expression dealing with log base 10 .
how can sal simply cancel out the log_10 ( c ) ?
so we have two different logarithmic expressions here , one in yellow and one in this pinkish color . and what i want you to do , like always , pause the video and see if you can re-write each of these logarithmic expressions in a simpler way . and i 'll give you a hint in case you have n't started yet . the hint is t...
now let 's try to , now let 's try to tackle this one over here . so i 've log base c of 16 , times log base two of c , alright . so this one , once again it might be nice to re-write these , each of these , as a rational expression dealing with log base 10 .
as log_10 ( c ) is in the denominator , does it matter whether log_10 ( c ) will equal zero or not ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
so this is equal to .2 molar . that was the original concentration of iron two plus ions in solution . you could have used the mv is equal to mv equation and modified it , because our ratio is n't one to one here .
is it that it 's providing free hydrogen ions that transfer the electrons between the manganese and iron ions ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
to solve for the concentration of iron two plus , we just take how many moles of iron two plus we have , which is .002 , so we have .002 moles of iron two plus . we started with a total volume of 10 milliliters , which is equal to .01 liters . so we have .01 liters here .
why do you use only 10 ml instead of the total 30 ml to calculate the molarity ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
next , we need to figure out how many moles of iron two plus that we originally started with . to do that , we need to use our balance redox reaction . we 're going to look at the coefficients , because the coefficients tell us mole ratios .
when you were finding the mol for mno4 why did you use 20ml instead 10ml ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
down here , we have a source of permanganate anions . we 're going to drip in the potassium permanganate solution . when we do that , we 're going to get a redox reaction .
the potassium ( k+ ) in the potassium permangenate isnt going to mess up the titration outcome with its positive charge ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
so we have .01 liters here . and .002 divided by .01 is equal to .2 . so this is equal to .2 molar . that was the original concentration of iron two plus ions in solution .
why does the fe^2+ turn into fe^3+ when reacted with mno4^- ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
manganese has an oxidation state of plus seven . over here , for our products , we 're going to make mn two plus . manganese two plus cation in solution , so the oxidation state is plus two .
how do i predict these reactions when products are not given ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
let 's look at some oxidation states really quickly so we can see that this is a redox reaction . for oxygen , it would be negative two . we have four oxygens , so negative two times four is negative eight .
would n't it mean that now there are extra ions which would contribute to an extra volume , and therefore become an inaccurate value to calculate the concentration ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
down here , we have a source of permanganate anions . we 're going to drip in the potassium permanganate solution . when we do that , we 're going to get a redox reaction .
what exactly is referred to 'strength ' of a potassium permanganate solution ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
when we do that , we 're going to get a redox reaction . here is the balanced redox reaction . if you 're unsure about how to balance a redox reaction , make sure to watch the video on balancing redox reactions in acid . let 's look at some oxidation states really quickly so we can see that this is a redox reaction .
is there a video relating cell potentials with redox titrations ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
that means we 've completely reacted all the iron two plus that we originally had present . so we stop our titration at this point . we 've reached the endpoint .
how are the results and calculations affected if too much of the titrant - beyond the equivalence point - is titrated into the beaker ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
next , we need to figure out how many moles of iron two plus that we originally started with . to do that , we need to use our balance redox reaction . we 're going to look at the coefficients , because the coefficients tell us mole ratios .
so just to be clear you need to find the net redox reaction before you find the fe2+ right ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
when we do that , we 're going to get a redox reaction . here is the balanced redox reaction . if you 're unsure about how to balance a redox reaction , make sure to watch the video on balancing redox reactions in acid . let 's look at some oxidation states really quickly so we can see that this is a redox reaction . f...
do end point and equivalence point always coincide in redox titrations if the entity responsible for color change is itself involved in the reaction ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
in here , we 're going to have some potassium permanganate , kmno4 . let 's say the concentration of our potassium permanganate is .02 molar . that 's the concentration that we 're starting with .
i did n't quite understand why they calculate the molar mass and use it to represent concentration ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
we 've already seen how to do an acid-base titration . now let 's look at a redox titration .
what of the ones using reducing agents ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
that 's an increase in the oxidation state . iron two plus is being oxidized in our redox reaction . as we drip in our potassium permanganate , we 're forming our products over here .
why do those redox titrations usually have to happen in two steps ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
the molarity of permanganate is .02 . we have .02 for the concentration of permanganate ions . moles is what we 're solving for .
if there are access permanganate ions in the solution , why we can still use the the delta v as the proper v of permanganate ions that is needed in the reaction ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
as we drip in our potassium permanganate , we 're forming our products over here . these ions are colorless in solution . as the permanganate reacts , this purple color disappears and we should have colorless , we should have a colorless solution .
is the addition drop of the solution count into the delta v ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
that 's the concentration that we 're starting with . potassium permanganate is , of course , the source of permanganate anions , because this would be k plus and mno4 minus . down here , we have a source of permanganate anions .
for eg k2cr2o7 forms k positive cr positive ... im confused ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
as we drip in our potassium permanganate , we 're forming our products over here . these ions are colorless in solution . as the permanganate reacts , this purple color disappears and we should have colorless , we should have a colorless solution .
how can the mixture be colourless if there are coloured ions in there ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
as we drip in our potassium permanganate , we 're forming our products over here . these ions are colorless in solution . as the permanganate reacts , this purple color disappears and we should have colorless , we should have a colorless solution .
why do we add only sulfuric acid solution to provide h+ ions or acidic medium instead of hcl solution ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
let 's say we have 10 milliliters of our solution , and let 's say it 's an acidic solution . you could have some sulfuric acid in there . in solution , we have iron two plus cations and a source of protons from our acid .
how to find the n-factor when the compound acts as an acid but at the same time is a oxidizing agent also ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations .
in iodine titration to find out tin content of the fruit juices in tin cans , does the ascorbic acid in the fruit juice interfere with the values obtained ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
let 's say we have 10 milliliters of our solution , and let 's say it 's an acidic solution . you could have some sulfuric acid in there . in solution , we have iron two plus cations and a source of protons from our acid .
if so how to counteract the ascorbic acid so that only tin is measured ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
when we do that , we 're going to get a redox reaction . here is the balanced redox reaction . if you 're unsure about how to balance a redox reaction , make sure to watch the video on balancing redox reactions in acid . let 's look at some oxidation states really quickly so we can see that this is a redox reaction . f...
how to write a redox reaction when given a statement form of it ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
let 's say we have 10 milliliters of our solution , and let 's say it 's an acidic solution . you could have some sulfuric acid in there . in solution , we have iron two plus cations and a source of protons from our acid .
how will kmno4react with acid alkaline and neutral medium ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
let 's get some more room down here . we know that molarity is equal to moles over liters . the molarity of permanganate is .02 .
how will we know the chemical equation ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
if we 're going to find the concentration of iron two plus , we could figure out how many moles of permanganate were necessary to completely react with our iron two plus . we could figure out moles from molarity and volume . let 's get some more room down here .
instead of going through all of those steps , could n't you have used the solution dilation equation ( m1*v1 ) /coefficient = ( m2*v2 ) /coefficient , where m1 and v1 are the molarity and volume of one solution and m2 and v2 are the molarity and volume of the other ?
we 've already seen how to do an acid-base titration . now let 's look at a redox titration . let 's say we have a solution containing iron two plus cations . we do n't know the concentration of the iron two plus cations , but we can figure out the concentration by doing a redox titration . let 's say we have 10 milli...
five times .0004 is equal to .002 . x is equal to .002 . x represents the moles of iron two plus that we originally had present .
and just plug in the known values ( v1 = 0.0200m , m1 = 0.020l , v2 = 0.010l , and m1 = x ) and their coefficients to get 0.0200m*0.020l = ( 0.010l*x ) /5 and solve for x ?
: everything we 've discussed so far involved recognizing and tagging or engulfing shady things that were found outside of cells . we 've seen things like a b cell . a b cell has its membrane bound antibodies . maybe one of these might recognize something shady out in the outside of the cell and of course this part ov...
it will wreck some of the antigens that are being produced inside by the viruses . they 're going to bind to mhc one complexes . pieces of the virus are going to bind to mhc one complexes and then they 're going to be presented on the surface .
so mhc i complexes are kind of like whistleblowers in companies that report anything shady ?
: everything we 've discussed so far involved recognizing and tagging or engulfing shady things that were found outside of cells . we 've seen things like a b cell . a b cell has its membrane bound antibodies . maybe one of these might recognize something shady out in the outside of the cell and of course this part ov...
this is a helper , t helper cell . when it recognizes then it will start dividing into memory helper t cells and effector helper t cells . the effector helper t cells essentially ring the alarm bells and start kind of accelerating the b cell replication or i guess you could say that the b cell activation .
are the cytoxic t cells working at the same time as the helper t cells ?
: everything we 've discussed so far involved recognizing and tagging or engulfing shady things that were found outside of cells . we 've seen things like a b cell . a b cell has its membrane bound antibodies . maybe one of these might recognize something shady out in the outside of the cell and of course this part ov...
for example a cell like this all ready , so that 's its nucleus . it 's already been infected by some virus so the virus has hijacked the cell 's replication machinery in order to replicate itself . the proper immune response is hey look , i 'm a virus making machine .
is there any virus that stops the major histocompatibility complexes to stop presenting parts of the virus ?