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957247
Evaluate $$\displaystyle\int \frac{dx}{\sin x + \sec x}$$
\frac2{\sqrt3} \tanh^{-1}(\sqrt{\frac23}\sin\frac t2)-2\tan^{-1}(\sqrt2\cos\frac t2)+C
Expression
Mathematics
University
641430
Multiply $\left( \begin{array}{c} -\frac{1}{2} \\ -\frac{1}{3} \\ -\frac{1}{2} \\ \frac{3}{2} \\ \frac{11}{6} \\ \end{array} \right)$ and $\left( \begin{array}{ccccc} -\frac{8}{3} & \frac{7}{6} & 0 & -\frac{1}{6} & \frac{3}{2} \\ \end{array} \right)$.
\begin{pmatrix} \frac{4}{3} & -\frac{7}{12} & 0 & \frac{1}{12} & -\frac{3}{4} \\ \frac{8}{9} & -\frac{7}{18} & 0 & \frac{1}{18} & -\frac{1}{2} \\ \frac{4}{3} & -\frac{7}{12} & 0 & \frac{1}{12} & -\frac{3}{4} \\ -4 & \frac{7}{4} & 0 & -\frac{1}{4} & \frac{9}{4} \\ -\frac{44}{9} & \frac{77}{36} & 0 & -\frac{11}{36} & \fr...
Matrix
Mathematics
University
1273654
Set up an initial value problem that can be solved for the amount {eq}\displaystyle \rm A {/eq} of salt in the tank at time {eq}\displaystyle t {/eq}.
dA/dt = 1 - 2A/(240-t), A(0) = 60
Expression
Mathematics
University
546690
What time is Emma by Jane Austen set in?
late 18th century
String
Other
Junior High School
111213
What is the present value of $13,150 to be received 4 years from today if the discount rate is 5 percent?
$10,818.51
Float
Finance
Senior High School
344166
Differentiate the function {eq}f(x) = x^{4x^2}{/eq} with respect to {eq}x{/eq}.
4x^(4x^2 + 1) ( 2 \ln x + 1 )
Expression
Mathematics
University
709865
Solve $\frac{\mathrm{d} y}{\mathrm{d} x} = 2 + \sqrt{y - 2x + 3}$
{eq}y = \frac{1}{4}x^2 + (\frac{C}{2}+2)x + \frac{C^2}{4} - 3{/eq}
Expression
Mathematics
University
476855
When two point charges are a distance d part, the electric force that each one feels from the other has magnitude F. In order to make this force twice as strong, what would be the change in the distance? 1. {eq}\frac{d}{2} {/eq} 2. d 3. {eq}\frac{d}{4} {/eq} 4. 2d
{eq}\frac{d}{\sqrt{2}}{/eq}
Expression
Physics
Senior High School
670739
What type of structures of copolymers have a higher probability of crystallization?
Alternating and block copolymers
List
Chemistry
University
773222
A neutral molecule is identified as a tetrafluoride, {eq}\rm XF_4 {/eq}, where {eq}\rm X {/eq} is an unknown atom. If the molecule has a dipole moment of {eq}\rm 0.63\ D {/eq}, can you give some possibilities for the identity of {eq}\rm X {/eq}?
Sulfur
String
Chemistry
Senior High School
105263
How is the expression $$\frac{df}{dz}=\lim_{\delta z \to 0} \frac{f(z+\delta z)-f(z)}{\delta z}$$ transformed into $$\frac{df}{dz}=e^{-i\alpha}\left(\frac{\partial u}{\partial x}\cos (\alpha) +i\frac{\partial v}{\partial y}\sin (\alpha)\right)+\left(\frac{\partial u}{\partial y}\sin (\alpha) +i\frac{\partial v}{\partia...
\frac{df}{d\epsilon} = f_x\frac{dx}{d\epsilon} + f_y\frac{dy}{d\epsilon}
Expression
Mathematics
University
1945073
Convert the following matrix to reduced row echelon form: $\left( \begin{array}{cccc} 4 & -8 & -1 & 0 \\ 5 & -6 & 10 & -5 \\ 5 & 6 & 0 & 4 \\ \end{array} \right)$.
$\left(\begin{array}{cccc}1 & 0 & 0 & \frac{157}{350} \\0 & 1 & 0 & \frac{41}{140} \\0 & 0 & 1 & -\frac{96}{175} \\ \end{array}\right)$
Matrix
Mathematics
University
347517
Consider a four-year project with the following information: Initial fixed asset investment = $510,000; straight-line depreciation to zero over the four-year life; zero salvage value; price = $20; variable costs = $10; fixed costs = $150,000; quantity sold = 81,000 units; tax rate = 34 percent. How sensitive is OCF to ...
With a 1% increase in quantity sold, OCF increases by 1.116% With a 1% decrease in quantity sold, OCF decreases by 1.116%
Percentage
Business
University
217435
What structures direct lymph into the bloodstream?
The right lymphatic duct and the thoracic duct
List
Biology
Senior High School
949505
Which form of cancer in the female reproductive system ranks second in occurrence? A. Ovarian B. Cervical C. Endometrial D. Vaginal
A
Multiple Choice
Biology
Senior High School
1995478
How do you evaluate the integral of #[ (e^7x) / ((e^14x)+9) dx ]#?
{7/126(14/(9e^(-7x))-ln|14/(9e^(-7x))+1|) + C}
Expression
Mathematics
University
70552
How do you evaluate the integral #int (x-1)/(x+1)dx#?
x -2lnabs(x+1) +C
Expression
Mathematics
University
610416
Convert the following matrix to reduced row echelon form: $\left( \begin{array}{cccccc} 2 & -4 & 1 & 5 & 0 & 4 \\ 1 & -8 & 2 & 7 & -4 & 10 \\ -5 & 10 & 6 & -10 & -6 & -8 \\ \end{array} \right)$.
$\left(\begin{array}{cccccc}1 & 0 & 0 & 1 & \frac{4}{3} & -\frac{2}{3} \\0 & 1 & 0 & -\frac{23}{34} & \frac{25}{51} & -\frac{65}{51} \\0 & 0 & 1 & \frac{5}{17} & -\frac{12}{17} & \frac{4}{17} \\ \end{array}\right)$
Matrix
Mathematics
University
823476
The King Company is producing two types of products: A and B. Both products are produced on the same machining operation. The machines operate on two 8-hour shifts. 5 days a week and 50 weeks per year. The manager wants to. Maintain a 20% capacity cushion. The demand forecast, batch sizes, processing times, and setup t...
D
Multiple Choice
Business
University
989844
Auto Art sells original works of art on a prepaid basis as each piece is uniquely designed to the customer's specifications. For one project, the cash flows are $9,500 and -$10,300 for years 0 and 1, respectively. Based on the internal rate of return, should this project be accepted if the required return is 12 percent...
B
Multiple Choice
Business
University
1444884
Does cellular respiration happen in humans or just in plants?
both humans and plants
Boolean
Biology
Junior High School
778400
A farmer produces both corn and wheat. if he must give up 10 bushels of corn to get 15 bushels of wheat, then what is his opportunity cost of 1 bushel of wheat?
2/3 of a bushel of corn
Fraction
Economics
Senior High School
91446
What genre is The Devil in the White City?
Non-fiction
String
History
Junior High School
1447262
Find the double integral {eq}\iint_Ry^2dA, {/eq} where R is the region enclosed by y= 2 - x and {eq}y= x^2. Start by graphing the region R.
423/28
Fraction
Mathematics
University
1840152
Show that $\mathbb{R}^2-\{(0,0)\}$ is homeomorphic to $\mathbb{R}×S^1.$
The homeomorphism between $\mathbb{R}^2 \setminus \{0\}$ and $\mathbb{R} \times S^1$ can be established through the functions $f(p) = (\ln \lVert p \rVert, \frac{p}{\lVert p \rVert})$ and its inverse $g(x,z) = e^xz$.
Expression
Mathematics
University
1135445
How do I express the following optimization problem as either LP, QP, QCQP or SOCP? \begin{array}{ll} \text{minimise}_{x,y,t} & a||\mathbf{x}||_2^2 + b||\mathbf{y}||_2^2 \\ \text{subject to}& ||\mathbf{x}+\mathbf{y}||_2^2 \le t. \end{array} where $a,b \in \mathbb{R}_+$ and $\mathbf{x},\mathbf{y}\in \mathbb{R}^n$. Is my...
Minimize z subject to u <= t v = 1/2 w_i = x_i + y_i for all i 2uv >= sum_i w_i^2 2vz >= sum_i (sqrt(a)x_i)^2 + (sqrt(b)y_i)^2
Expression
Mathematics
University
201866
How large would your annual payments be for a 30-year, $110,000 amortized loan at a nominal annual rate of 7% with annual end-of-year payments?
$8,864.50
Float
Mathematics
University
1017313
How do you say 'seriously' in Spanish?
en serio
String
Other
Primary School
1566801
Find the area of the finite part of the paraboloid {eq}\; y = x^2 + z^2 \; {/eq} cut off by the plane {eq}\; y = 25 {/eq}.
530.95
Float
Mathematics
University
290080
A pendulum clock has a heavy bob supported on a very thin steel rod that is 1.00000 m long at 21.0. The clock keeps perfect time at 21.0 degree C. At 33.0 degree C after how many hours will the clock be off by 3.00 s?
11.9 h
Float
Physics
Senior High School
1375803
Calculate the volume of the cone whose radius is 3 units, height is 4 units and whose apex is at the origin in the xy-plane. Use spherical coordinates.
12π
Expression
Mathematics
University
680190
Operating data for Conard Corporation are presented below. 2014 2013 Net sales $751,930$603,830 Cost of goods sold 477,180412,330 Selling expenses 117,61083,130 Administrative expenses 74,87049,980 Income tax expense 35,85018,190 Net income 46,420 40,200 Prepare a schedule showing a vertical analysis for 2014 and 2...
Vertical Analysis 2014 Amount Percentage Net sales $751,930 100% Cost of goods sold 477,180 63.5% Gross profit 274,750 36.5% Selling expenses 117,610 15.6% Administrative expenses 74,870 10% Total operating expenses 192,480 25.6% Income before taxes 82,270 10.9% Income tax expense 35,850 4.8% Net income 46,420 6.1% 20...
List
Business
Senior High School
1289904
How long did the Scientific Revolution last?
1543 -1687
String
History
Junior High School
774752
Suppose you are buying your first home, a condominium, for $300,000. The down payment is $15,000 and you have arranged for a 30-year amortized mortgage at a 6.5% nominal rate of interest with the first payment due in one-month. If you pay an additional $500 per month in addition to the monthly payment, how soon will th...
206 months or 17.18 years
Float
Finance
University
2054284
A simple pendulum of length 1.0 meter with a bob of mass m swings with an angular amplitude of 60 degrees. What would be the tension in the string when its angular displacement is 45 degrees?
1.121mg
Expression
Physics
University
402510
Is it possible to calculate the radius of Earth based on two height measurements, and knowing the distance between the observers? If so: how? I have the following situation: Here I can use the Pythagorean theorem to find R = ($a^2/2s$)-$s/2$ but what if the observers are on 2 different heights? (Like the picture but yo...
If the line between the two observers is tangent to the Earth, the radius R can be calculated by solving d = sqrt{h1(h1+2R)} + sqrt{h2(h2 + 2R)}, where d is the distance between the two observers, and h1 and h2 are the heights of the two observers, respectively. If the line between the two observers is not tangent to ...
Expression
Physics
Senior High School
1730557
As the unemployment rate rises, A. the rate of voluntary turnover increases. B. early retirement plans become less attractive to Baby Boomers. C. people available for work tend to have high qualifications. D. it becomes harder to fill jobs with skilled workers.
C
Multiple Choice
Economics
Senior High School
1934476
Find all points of inflection for f(x) = tan(3x) on the domain (-π,π).
x=-2π/3, -π/3, 0, π/3, 2π/3
List
Mathematics
University
749759
Aerobic respiration uses oxygen to break down energy-rich food molecules and store their energy in the form of ATP. List the major inputs and outputs of aerobic respiration.
Inputs: Glucose and Oxygen Outputs: Carbon dioxide, Water, and 36 ATPs
List
Biology
Junior High School
1424188
What is the formula mass of water?
18.02 amu
Float
Chemistry
Junior High School
1034187
Let $P(x)$ be a real polynomial of degree 6 with the following property: For all $-1\leq x\leq 1$, we have $0\leq P(x)\leq 1$. what is the maximum possible value of the leading coefficient of $P(x)$?
16
Integer
Mathematics
University
178818
Find the volume of the solid whose base is the region bounded by the x-axis, the curve {eq}y=\sqrt{x^2+25} {/eq}, x=0 and x=2 and which has the property that each cross-section perpendicular to the x-axis is an equilateral triangle.
22.80533
Float
Mathematics
University
1113895
Imagine you are an astronaut who has landed on another planet and wants to determine the free-fall acceleration on that planet. In one of the experiments you decide to conduct, you use a pendulum 0.47 m long and find that the period of oscillation for this pendulum is 1.43 s. What is the acceleration due to gravity on ...
9.07 m/s^2
Float
Physics
Senior High School
290069
An annuity has an expected $900 payment annually for 4 years at an interest rate of 6%.What is the present value of the annuity?
$3,118.60
Float
Finance
Senior High School
1202286
Integrate (x^2 - 3 x - 4) e^{-2 x}\ dx and don't simplify.
- \frac{\left(x^2 - 2x - 5\right)e^{-2 x}}{2} + C
Expression
Mathematics
University
783176
If its tax rate is 30%, calculate the WACC or weighted average cost of capital. Jack has found a really cheap small cap food stock that markets snacks. It has 10 mm shares outstanding, a share price of $15, 40 mm in debt, and 10 mm in cash. It has a cost of debt of 10%. It expects to generate 30 mm in EBITDA, operatin...
10.95%
Percentage
Business
University
29145
Perform the indicated calculation: 35.453 g/mol + 1.0 g/mol Express your answer with the correct number of significant figures and include units. Don't forget to use the correct format for scientific notation.
36.4 g/mol
Float
Chemistry
Senior High School
1426136
What is the number in front of each molecule in a chemical equation that tells how many of each molecule is present?
coefficient
String
Chemistry
Junior High School
232985
Compute the present value of $1,200 received at the end of each year for the next six years discounted at 8% compounded annually.
$5548
Float
Mathematics
University
1483036
Why is the camel such an important animal in the middle east 1.(a) the camel can carry a large amount of people and goods 2.(b)the camel has an incredible ability to adapt to harsh conditions 3.(c)the camel is easily trained and very obedient 4.(5)the camel is extremely loyal to its owners
b
Multiple Choice
History
Primary School
1656422
1. The oversupply of hospitals and in-patient beds in the U.S. produced by the Hill-Burton legislation is the result of: A. The advent of managed care B. Change in the focus of medical education C. Technological advances D. Clinical guidelines E. A and C
E
Multiple Choice
History
University
1425285
Four identical particles, each having charge {eq}q {/eq} and mass {eq}m {/eq}, are released from rest at the vertices of a square of side {eq}L {/eq}. How fast is each particle moving when their distance from the center of the square doubles?
v = \sqrt{\frac{2.707kq^2}{mL}}
Expression
Physics
Senior High School
2096689
The following are selected accounts for the Alpha Dog Company after all Fiscal Year December 31, 2016, adjusting entries & closing entries have been posted. All balances are normal. Account Amount Common Stock, $5 par $150,000 Treasury Stock, at a cost $10 per share 20,000 Dividends Payable 5,000 Paid in Capital in e...
Alpha Dog Company Balance Sheet (partial) On December 31, 2016 Stockholders' Equity: Paid in Capital: Common stock, $5 par value, 50,000 shares authorized; 30,000 shares issued and 28,000 outstanding$150,000 Preferred Stock, $100 par, 5% cumulative, 5,000 shares authorized, 350 shares issued and outstanding 35,000 Pai...
List
Business
University
1149817
Compute the (pseudo)inverse of $\left( \begin{array}{ccc} -3 & -3 & 0 \\ -4 & -2 & -3 \\ 4 & -1 & 0 \\ \end{array} \right)$.
\frac{1}{45}\left( \begin{array}{ccc} -3 & 0 & 9 \\ -12 & 0 & -9 \\ 12 & -15 & -6 \\ \end{array} \right)
Matrix
Mathematics
University
1288890
How does $$(R^2 +[|x|]^2)^{0.5}$$ expand as $$R + \frac{[|x|]^2}{2R} + \text{(more terms)}$$ around the point $x = 0$?
$$R+\frac{x^2}{2 R}-\frac{x^4}{8 R^3} +\frac{x^6}{16 R^5}-\frac{5 x^8}{128 R^7}$$
Expression
Mathematics
University
806481
A child's achievement seems more influenced by _____ in the united states than in other nations.
income and ethnicity
String
Other
Senior High School
1443192
Find the theoretical yield of {eq}NaCl {/eq} using 0.016 mols {eq}HCl {/eq} with {eq}HCl + NaOH \rightarrow NaCl + H_2O {/eq} as the equation for the reaction.
0.016 mol
Float
Chemistry
Senior High School
949910
An 88-pound boy has a severe allergic reaction to a test allergen that has been administered. Which dosage of subcutaneous epinephrine would be appropriate for him?
0.4 mg
Float
Health
Senior High School
288225
Find the general solution for the differential equation \(\displaystyle \frac{\mathrm{d} y}{\mathrm{d} x} = y - 8\)
y = e^(x+c) + 8
Expression
Mathematics
University
858268
What are the steps that 1-pentyne goes through to become N-ethyl pentanamide?
1. Convert 1-pentyne to pentanal using H2SO4 and HgSO4 at 60°C. 2. Oxidize pentanal to pentanoic acid using KMnO4. 3. React pentanoic acid with ethylamine and heat to produce N-ethyl pentanamide.
List
Chemistry
University
492809
Which factors can affect the amount of friction acting on an object on a solid surface?
The mass of the object, the type of surface, and whether the object is still or moving are all factors that affect friction.
List
Physics
Junior High School
79840
A train starts from station A and for the first kilometer, it travels with a uniform acceleration. Then, for the next two kilometers, it travels with a uniform speed. Finally, the train decelerates uniformly for another kilometer before coming to rest at station B. If the time for the whole journey is six minutes, dra...
16.666 m/s
Float
Physics
Senior High School
1232438
How can I solve the equation $\dfrac x9 = \log_2x$ ?
x = $e^{-W(-\frac{ln(2)}{9})}$ , $e^{-W_{-1}(-\frac{ln(2)}{9})}$
Expression
Mathematics
University
1368363
If I'm evaluating $\int^b_a r dz$, where $r$ is a variable in spherical coordinates and $z$ is a variable in rectangular coordinates, do I need to transform $dz$ in spherical coordinates? If so, how would I do that?
z = rcos(φ), dz = cos(φ)dr - rsin(φ)dφ
Expression
Mathematics
University
1136770
Use the Laplace transform to solve the problem {eq}y'' + 6y' + 34y = 0, y(0) = 3, y'(0) = 1 {/eq}.
y(t) = 3e^(-3t)cos(5t) + 2e^(-3t)sin(5t)
Expression
Mathematics
University
1709035
What is the Taylor series of f(x) = 1/x about x = 2?
{eq}f(x)= \sum_{n=0}^{\infty} \frac{(-1)^n (x-2)^n } { 2^{n+1} }{/eq}
Expression
Mathematics
University
1421193
Given that one solution of {eq}x^2 y'' + 6x y' + 4y = 0 {/eq} is {eq}\displaystyle \frac{1}{x} {/eq}, use reduction of order to find the second linearly independent solution.
-1/(3x^4)
Expression
Mathematics
University
1703453
If I have two sets of data, x and y, and I am required to apply a weighting factor, 1/x, to the regression line, does that mean I should plot 1/y versus 1/x and then get the regression?
Compute \(\frac{dSSQ}{da}\) and \(\frac{dSSQ}{db}\) for \(SSQ=\sum_{i=1}^n \frac 1{x_i}(a+bx_i-y_i)^2\), and set them to be zero. This gives two linear equations to solve for the two unknowns \(a\) and \(b\).
Expression
Mathematics
University
415815
What is the gravitational force on a 60 k person on the earth, due to the moon?
0.002 N
Float
Physics
Senior High School
441446
Is the following table for $D_4$ correct? $$\begin{array}{c|c|c|c|c|c|c|c|c|} * & 1 & g & g^2& g^3& f& fg & fg^2 & fg^3 \\ \hline 1 & 1 & g & g^2 & g^3 & f & fg & fg^2 & fg^3 \\ \hline g & g & g^2 & g^3 & 1 & fg^3 & f & fg & fg^2 \\ \hline g^2 & g^2 & g^3 & 1 & g & fg^2 & fg^3 & f & fg \\ \hline g^3 & g^3 & 1 & g & g^2...
Yes
Boolean
Mathematics
University
1527949
What mass in grams would 5.7L of hydrogen gas occupy at STP?​
0.54 g
Float
Chemistry
Senior High School
469620
Sagon Corporation manufactures and sells one product. The following information pertains to the company's first year of operations: The company does not have any variable manufacturing overhead costs or variable selling and administrative costs. During its first year of operations, the company produced 29,000 units ...
b
Multiple Choice
Business
University
604257
Given two aqueous solution whose respective #pH# values are #6# and #3#, how much more acidic is one solution compared to the other?
1000
Integer
Chemistry
Senior High School
1345673
A sphere of radius {eq}R {/eq} and surface charge density {eq}\eta {/eq} is positioned with its center distance {eq}2R {/eq} from an infinite plane with surface charge density {eq}\eta {/eq}. (a) At what distance from the plane, along a line toward the center of the sphere, is the electric field zero? Expres...
x =(2 - √2)R
Expression
Physics
University
369032
This 30-year-old female comes to the clinic because of excessive vomiting for the last three days. She is in her 24th week and has had no problems with vomiting in her early pregnancy. What is the correct diagnostic code assignment for this case? ICD-10-CM Code(s):
O21.9
String
Health
Senior High School
703858
A regulated natural monopoly is most likely to spend more money on employee healthcare under which of the following types of regulation? Select one: a. All of the above. b. Administrative regulation. c. Price regulation. d. Profit regulation.
a
Multiple Choice
Economics
University
1295262
At which of these points is an insurance contract accepted? a. When the first premium is paid. b. When the application is received. c. When the binder is delivered. d. When the insurance company has had enough time to review the application.
a
Multiple Choice
Finance
Senior High School
307155
By switching to polar coordinates, evaluate the integral {eq}\iiint_D (x^2+y^2)^{7/2} \,dx \,dy where {eq}D is the disk {eq}x^2+y^2=4^2
{eq}\frac{2(4^9)\pi}{9}{/eq}
Fraction
Mathematics
University
289592
Find the eigenvalues of the following matrix: $\left( \begin{array}{ccc} 3 & 7 & -5 \\ 1 & 2 & 5 \\ -1 & 6 & 8 \\ \end{array} \right)$.
$\lambda = -3.15131$ or $\lambda = 4.86343$ or $\lambda = 11.2879$
Float
Mathematics
University
793514
AAA Company is about to issue a bond with semiannual coupon payments, an annual coupon rate of 8%, and par value of $1,000. The yield to maturity for this bond is 6?%. What is the price of the bond if it matures in 5 years?
$1,085.30
Float
Finance
University
864562
Evaluate the right Riemann sum for f(x)=x+1 on [0, 4] with n=50.
12.16043
Float
Mathematics
University
36890
Did Sam Shepard talk against gays before coming out himself?
No
Boolean
History
Junior High School
489608
Rewrite the integral with limits of integration {eq}i = 0{/eq} to {eq}1{/eq}, radical {eq}x{/eq} to {eq}1{/eq} , {eq}0{/eq} to {eq}1-y{/eq}, dz dy dx in the order {eq}dx dy dz{/eq}
{eq}I= \int_{0}^{1}\int_{0}^{1-z}\int_{0}^{y} dx dy dz{/eq}
Expression
Mathematics
University
1846053
Expand the function {eq}\displaystyle f (x) = \begin{cases}-1,& -\pi < x < 0\\ 1, &0 \le x \lt \pi \end{cases} {/eq} in an appropriate cosine or sine series.
f(x)=1+(4/π)∑_{n=0}^{∞}[sin((2n+1)x)/(2n+1)]
Expression
Mathematics
University
1243369
Find a matrix where the kernel is a subspace of the range. Is the following correct? The matrix I had in mind: $$\begin{bmatrix}1&0&0\\0&1&0\\0&0&1\end{bmatrix}$$ In this case, we see that the kernel is made up of a single vector, namely the zero vector, as that's the only solution that maps to the zero object. Next, w...
A = BC^T, where B = [[1, 0], [0, 1], [0, 0]] and C = [[0, 0], [1, 0], [0, 1]]
Matrix
Mathematics
University
1693414
How can I prove that for $d=2$, $v_2=2\int_{-1}^1 (1-x^2)^{1/2} \, dx$ using Corollary 3.8, and hence that $v_2=\pi$, given that $m(B)=v_2 r^2$, $v_2=\frac{m(B)} r^2$, and Corollary 3.8 states that if $\mathcal A = \{(x,y) : \mathbb R^d \times \mathbb R : 0 \le y \le f(x)\}$, then $\int_{\mathbb R^d} f(x) \, dx = m(\ma...
$v_2=2\int_{-1}^1\sqrt{1-x^2}dx$.
Expression
Mathematics
University
1312730
What is #f(x) = int x-xsec(x/2) dx# if #f((7pi)/4) = 0#?
#4i(Li_2(-ie^((ix)/2)) - Li_2(ie^((ix)/2))) +x^2/2-2x(ln(1-ie^((ix)/2)) - ln(1+ie^((ix)/2))) +C#
Expression
Mathematics
University
208351
Evaluate the following integral: {eq}\; \int \frac{\sqrt{36x^2 - 49}}{x^3} \, \mathrm{d}x, \; x > \frac{7}{6} {/eq}.
{eq}\frac{54 }{25} \left( 2 arcsec(6x/7) - \sin \left( arcsec(6x/7) \right) \right)+C{/eq}
Expression
Mathematics
University
849773
Given the differential equation dP/dT = KP(P-K)(L-P), where K and L are unequal constants, is it possible to analytically find a solution only in terms of P, without assuming L > K > 0? How would one go about solving the equation then?
e^{-KT}+C=P^{\frac{1}{KL}}(P-K)^{\frac{1}{K(K-L)}}(P-L)^{\frac{1}{L(L-K)}}
Expression
Mathematics
University
1824578
A 16 ft ladder leans against a wall. The bottom of the ladder is 4 ft from the wall at time t = 0 and slides away from the wall at a rate of 3 ft/sec. Find the velocity of the top of the ladder at time t = 3.
-4.18 ft/s
Float
Physics
Senior High School
1159610
When a company changes from an accelerated method to the straight-line method of depreciation, this change should be handled as a: A. change in accounting estimate B. prior period adjustment C. correction of an error D. change in accounting principle
A
Multiple Choice
Business
University
119746
A basketball player tries to make a half-court jump shot, releasing the ball at the height of the basket. Assuming that the ball is launched at {eq}51.0^{\circ} {/eq}, 14.0 m from the basket, what speed must the player give the ball?
11.849 m/s
Float
Physics
Senior High School
814853
A point charge +6.8 {eq}\mu {/eq}C is placed at the origin, and a second charge -4.5 {eq}\mu {/eq}C is placed in the x -y plane at (0.35 m, 0.50 m ). Where should a third charge be placed in the plane so that the net force acting on it is zero? Express your answers using two significant figures. Enter the x and y coo...
1.9 m, 2.7 m
Expression
Physics
University
50500
How much work must be done to stop an {eq}\rm 1150-kg {/eq} car traveling at {eq}\rm 125 \ km/h {/eq}? Express your answer to two significant figures and include the appropriate units.
-6.9e+05 J
Float
Physics
Senior High School
2104274
A woman and her dog are out for a morning run to the river, which is located 4.03 km away. The woman runs at 3.88 m/s in a straight line. The dog is unleashed and runs back and forth at 5.63 m/s between his owner and the river, until she reaches the river. What is the total distance run by the dog (in meters)?
5847.6 m
Float
Physics
Senior High School
271425
What two factors have the greatest influence on soil formation?
Temperature and rain
List
Other
Junior High School
898405
Two circular coils are concentric and lie in the same plane. The inner coil contains 120 turns of wire, has a radius of 0.012m, and carries a current of 6.5A. The outer coil contains 160 turns and has a radius of 0.017m. What must be the magnitude and direction (relative to the current in the inner coil) of the current...
6.90 A
Float
Physics
Senior High School
1974654
A stone was dropped off a cliff and hit the ground with a speed of {eq}90 \frac {ft}{s}. {/eq} What is the height of the cliff. (the downward acceleration from gravity is {eq}32 \frac {ft}{s^2} {/eq})
126.5625 ft
Float
Physics
Senior High School
219945
Compute the (pseudo)inverse of $\left( \begin{array}{cc} -\frac{1}{8} & -\frac{11}{4} \\ \frac{71}{16} & -\frac{19}{16} \\ \end{array} \right)$.
\frac{8}{1581}\left( \begin{array}{cc} -19 & 44 \\ -71 & -2 \\ \end{array} \right)
Matrix
Mathematics
University
97078
Find the volume of the solid generated by revolving the region defined by {eq}y=3, \ y=\sqrt{3x}{/eq}, and the {eq}y{/eq}-axis about the line {eq}x=-1{/eq}.
\frac{57\pi}{5}
Fraction
Mathematics
University