Wednesday

July 29, 2015

July 29, 2015

**Pre - CALCULUS**

Solve the system by the substitution method. Show your work. 2y - x = 5 x2 + y2 - 25 = 0
*Monday, April 13, 2015 by Ciara*

**Pre - CALCULUS**

Locate the foci of the ellipse. Show your work. 𝑥2/36+ y2/11=1
*Monday, April 13, 2015 by Ciara*

**pre - CALCULUS**

Find the indicated sum. Show your work. 4 k=1 (-1)^k(k+11) ￼Inbetween the 4 and k , Theres a backwards 3 sign
*Monday, April 13, 2015 by Ciara*

**Pre-Calculus**

Have I converted correctly from standard form to vertex form? y = -3x^2 + 12x+1 = y = -3(x-2)^2 -13 Thanks
*Monday, April 13, 2015 by Lucina*

**PRE - CALCULUS**

Eliminate the parameter t. Find a rectangular equation for the plane curve defined by the parametric equations. x = 6 cos t, y = 6 sin t; 0 ≤ t ≤ 2π A. x2 - y2 = 6; -6 ≤ x ≤ 6 B. x2 - y2 = 36; -6 ≤ x ≤ 6 C. x2 + y2 = 6; -6 ≤ x &#...
*Sunday, April 12, 2015 by Ciara*

**calculus rates**

The altitude (i.e., height) of a triangle is increasing at a rate of 2 cm/minute while the area of the triangle is increasing at a rate of 4 square cm/minute. At what rate is the base of the triangle changing when the altitude is 10.5 centimeters and the area is 97 square ...
*Sunday, April 12, 2015 by Anonymous*

**Pre-calculus **

The sum of the first two terms of an arithmetic series is 13 and the sum of the four terms is 46. Determine the first six terms of the series and the sum of the first six terms.
*Sunday, April 12, 2015 by Tawana *

**Pre-calculus**

Can someone please help me with this problem.. I don't get it! Solve (sqrt 5r - 9)-3 = sqrt(r+4)-2
*Saturday, April 11, 2015 by Lucina*

**pre - CALCULUS**

Use Gaussian elimination to find the complete solution to the system of equations, or state that none exists. x + y + z = 9 2x - 3y + 4z = 7 x - 4y + 3z = -2 A. {(-7z/5+34/5 ,2z/5 +11/5 , z)} b. {(- 7z/5+34/5 , 2z/5- 11/5 , z)} c . {( z/5+ 34/5 , 2z/5+11/5 , z)} C?
*Saturday, April 11, 2015 by Ciara*

**Pre - CALCULUS**

Find the inverse of the matrix, if possible. A = { 0 -6 } {-2 -5} A. 0 -1/2 -1/6 5/12 B. -1/6 0 5/12 - 1/2 C. 5/12 - 1/2 -1/6 0 D. 5/12 1/2 1/6 0 C ?
*Saturday, April 11, 2015 by Ciara*

**Pre - CALCULUS**

Use Cramer's rule to solve the system. 2x + 4y - z = 32 x - 2y + 2z = -5 5x + y + z = 20 A. {( 1, -9, -6)} B. {( 2, 7, 6)} C. {( 9, 6, 9)} D. {( 1, 9, 6)} d ?
*Saturday, April 11, 2015 by Ciara*

**Calculus**

The altitude (i.e., height) of a triangle is increasing at a rate of 2 cm/minute while the area of the triangle is increasing at a rate of 4 square cm/minute. At what rate is the base of the triangle changing when the altitude is 10.5 centimeters and the area is 97 square ...
*Saturday, April 11, 2015 by Anonymous*

**pre - CALCULUS**

Let B = [-1 3 6 -3]. Find -4B. A. [-4 12 24 -12] B. [-3 1 4 -5] C. [4 -12 -24 12] D. [4 3 6 -3] b ?
*Saturday, April 11, 2015 by Ciara*

**pre - CALCULUS**

Use Cramer's rule to determine if the system is inconsistent system or contains dependent equations. 2x + y = 8 6x + 3y = 24 A. system is inconsistent B. system contains dependent equations b ?
*Saturday, April 11, 2015 by Ciara*

**pre - CALCULUS**

Solve the system by the method of your choice. Identify systems with no solution and systems with infinitely many solutions, using set notation to express their solution sets. x + y = -8 x - y = 14 A. {( 3, -11)} B. {( 3, 11)} C. {(x, y) | x + y = -8} D. ∅ B?
*Saturday, April 11, 2015 by Ciara*

**calculus**

A cylindrical drum with an open top is to be constructed using 1 m^2 of aluminum a)write and equation for the volume of the drum in terms of radius b)what radius gives the direct maximum value? c)What is the maximum volume if the radius can be a maximum of 0.2m ? c)
*Saturday, April 11, 2015 by lotus*

**Calculus(easy)**

Suppose the derivative of a function f is f′(x)=(x−5)^3(x−3)^4(x+18)^8. Then the function f is increasing on the interval Can anyone please help me with this problem. It seems simple, but I just do not understand it.
*Friday, April 10, 2015 by Ryan kustin*

**Calculus(urgent please help)**

Consider the following function f(x)=x^2/[x^2-9] f(x) is increasing on the interval(s) f(x) is decreasing on the interval(s) f(x) has 2 vertical asymptotes x= f(x) is concave up on the interval(s) f(x) concave down on the interval(s) I've been stuck on these parts, I ...
*Friday, April 10, 2015 by Ryan kustin*

**pre - CALCULUS**

Complete the following: (a) Use the Leading Coefficient Test to determine the graph's end behavior. (b) Find the x-intercepts. State whether the graph crosses the x-axis or touches the x-axis and turns around at each intercept. Show your work. (c) Find the y-intercept. ...
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Use the compound interest formulas A = Pert and A = P(1 + 𝑟/n)^nt to solve. Suppose that you have $11,000 to invest. Which investment yields the greater return over 10 years: 6.25% compounded continuously or 6.3% compounded semiannually? Show your work.
*Friday, April 10, 2015 by Ciara*

**Pre - CALCULUS**

For the data set shown by the table, a. Create a scatter plot for the data. (You do not need to submit the scatter plot) b. Use the scatter plot to determine whether an exponential function or a logarithmic function is the best choice for modeling the data. Number of Homes ...
*Friday, April 10, 2015 by Ciara*

**Pre-calculus help**

I have two problems I am stuck on, if you could show me how to solve the problems it would be much appreciated. 1) Find sin 2x, cos 2x, and tan 2x from the given information. tan x = − 1/6, cos x > 0 sin 2x = cos 2x = tan 2x = 2) Find sin 2x, cos 2x, and tan 2x from ...
*Friday, April 10, 2015 by Holly*

**pre - CALCULUS**

Begin by graphing the standard absolute value function f(x) = | x |. Then use transformations of this graph to describe the graph the given function. h(x) = 2 | x | + 2
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Find the specified vector or scalar. Show your work. u = -4i + 1j and v = 4i + 1j; Find ‖𝑢 + 𝑣‖.
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Find functions f and g so that h(x) = (f ∘ g)(x). h(x) = (6x - 14)8
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Begin by graphing the standard absolute value function f(x) = | x |. Then use transformations of this graph to describe the graph the given function. h(x) = 2 | x | + 2
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Find the reference angle for the given angle. Show your work. -404° my answer is 44 degree , But i don't know how to put my work together..
*Friday, April 10, 2015 by Ciara*

**pre - CALCULUS**

Find functions f and g so that h(x) = (f ∘ g)(x). h(x) = (6x - 14)8
*Friday, April 10, 2015 by Ciara*

**Calculus I **

Hello, The pressure P and volume V of an expanding gas are related by the formula PVb=C, where b and C are constants (this holds in adiabatic expansion, without heat gain or loss). Find dPdt if b=1.6, P=12kPa, V=80cm2, and dVdt=20cm3/min. Thus far, I got d(PV)/dt= p(dv/dt) + V...
*Friday, April 10, 2015 by Natalie *

**Calculus**

Consider the following function f(x)=x^2/[x^2-9] f(x) is increasing on the interval(s) f(x) is decreasing on the interval(s) f(x) has 2 vertical asymptotes x= f(x) is concave up on the interval(s) f(x) concave down on the interval(s) I've been stuck on these parts for ...
*Friday, April 10, 2015 by Ryan kustin*

**Pre - CALCULUS**

Find the x-intercepts (if any) for the graph of the quadratic function. 6x2 +12x+5=0 Give your answers in exact form. Show your work.
*Friday, April 10, 2015 by Ciara*

**Calculus **

A road perpendicular to a highway leads to a farmhouse located 6 mile away. An automobile traveling on the highway passes through this intersection at a speed of 55mph. How fast is the distance between the automobile and the farmhouse increasing when the automobile is 2 miles ...
*Friday, April 10, 2015 by Nicole*

**Calculus**

Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 7.5 mi^2/hr. How rapidly is radius of the spill increasing when the area is 8 mi^2? I tried using A=(pi)r^2 and dA/dt=2(pi)r(dr/dt) and plugging in 7.5=2(pi)8(dr/dt) but the ...
*Friday, April 10, 2015 by Ashley*

**Calculus**

A snowball melts at a rate of 2 cubic inch an hour. When the volume is 36π in^3, how fast is the radius shrinking? V=(4/3)(pi)(r^3)
*Friday, April 10, 2015 by Anonymous*

**Calculus**

The outside radius of a thin open-ended cylindrical shell (of height 10 feet) is 12 feet. If the shell is 1 inch thick, use differentials to approximate the volume of the region interior to the shell.
*Friday, April 10, 2015 by Anonymous*

**pre - CALCULUS**

The wind chill factor represents the equivalent air temperature at a standard wind speed that would produce the same heat loss as the given temperature and wind speed. One formula for computing the equivalent temperature is 𝑡 W(t) = {33 − (10.45+10√𝑣...
*Thursday, April 9, 2015 by Ciara*

**pre - CALCULUS**

Verify the identity. Show your work. (1 + tan2u)(1 - sin2u) = 1
*Thursday, April 9, 2015 by Ciara*

**pre - CALCULUS**

The wind chill factor represents the equivalent air temperature at a standard wind speed that would produce the same heat loss as the given temperature and wind speed. One formula for computing the equivalent temperature is 𝑡 W(t) = {33 − (10.45+10√𝑣...
*Thursday, April 9, 2015 by Ciara*

**pre - CALCULUS**

A gas company has the following rate schedule for natural gas usage in single-family residences: Monthly service charge Per therm service charge 1st 25 therms Over 25 therms $8.80 $0.6686/therm $0.85870/therm What is the charge for using 25 therms in one month? Show your work...
*Thursday, April 9, 2015 by Ciara*

**pre - CALCULUS**

Verify the identity. Show your work. cot θ ∙ sec θ = csc θ
*Thursday, April 9, 2015 by Ciara*

**Calculus**

During a certain epidemic, the number of people that are infected at any time increases at rate proportional to the number of people that are infected at that time. 1,000 people are infected when the epidemic is first discovered, and 1,200 are infected 7 days later. Write and ...
*Thursday, April 9, 2015 by Anonymous*

**Calculus**

The number of people that hear a rumor follows logistic growth. In a school of 1500 students, 5 students start a rumor. After 2 hours, 120 students have heard about the rumor. Recall: dy/dx=ky(1-Y/L) and y=L/(1+be^(-kt)) I found the logistic growth equation to be 1500/(1+299e...
*Thursday, April 9, 2015 by Anonymous*

**Calculus**

Find the particular solution (solved for y) for the differential equation dy/dx=2x/e^(2y) satisfying y(0)=1.
*Thursday, April 9, 2015 by Anonymous*

**Calculus**

A manufacturer has determined that the weekly profit from the sale of x items is given by the function below. It is estimated that after t days in an week, x items will have been produced. Find the rate of change of profit with respect to time at the end of 7 days. P9x) = -x^2...
*Thursday, April 9, 2015 by Stacey *

**CALCULUS **

Consider the function f(x)=9x3−4x5. Let F(x) be the antiderivative of f(x) with F(1)=0. Then F(4) =
*Thursday, April 9, 2015 by Anonymous*

**Calculus**

Suppose that y=f(x) = sqrt(2x), x>=0 Find a c > 0 such that the tangent line to the curve y = f(x) at x = c has the same slope as the tangent line to the curve y = f^–1(x) at x = c. You get: c = 1/8 c = 1/2 c = (1/8)^(1/3) c = (1/3)^(2/3) c = (1/2)^(1/3)
*Thursday, April 9, 2015 by Thomas*

**Calculus AB**

For the function f(x) = sqrt(9-x), which is equal to d/dx(f-1( -1 is the inverse)(x)) a) -2x b) sqrt(x) + 9 c) x^2 + 9 d) 2x e) 9-x^2
*Thursday, April 9, 2015 by Thomas*

**Calculus**

For the function f(x) = x^2 - 4x +5, x>= 2, which is equal to d/dx (f-1 this is the inverse)(x)) ? 1/(2y-4) where x and y are related by the equation (satisfy the equation) x=y^2-4y+5 x>= 1 2y-4 where x and y are related by the equation y= = x^2 - 4x +5, x>= 2 1/2x-4 ...
*Thursday, April 9, 2015 by Thomas*

**Calc AB**

Remember that f(x) must be one-to-one (only one y-value for each x-value) over the domain where f –1(x)is defined as a function. So, in some cases you must restrict the domain of f(x) so that it's one-to-one. There might be more than one section of domain that's ...
*Thursday, April 9, 2015 by Thomas*

**Calculus**

Batman was driving the Batmobile at 90 mph (=132 ft/sec), when he sees a brick wall directly ahead. When the Batmobile is 400 feet from the wall, he slams on the brakes, decelerating at a constant rate of 22ft/sec2. Does he stop before he hits the brick wall? If so, how many ...
*Thursday, April 9, 2015 by Meme *

**Calculus**

A rectangular storage container with an open top is to have a volume of k cubic meters. The length of its base is twice its width. The material for the base costs $6 per square meters and the material for the sides costs $10 per square meter.
*Thursday, April 9, 2015 by Joseph*

**Calculus**

In a poll of 400 voters in a certain state, 61% said that they opposed a voter ID bill that might hinder some legitimate voters from voting. The margin of error in the poll was reported as 4 percentage points (with a 95% degree of confidence). Which statement is correct? A. ...
*Thursday, April 9, 2015 by Scott*

**Calculus**

Joe dealt 20 cards from a standard 52-card deck, and the number of red cards exceeded the number of black cards by 8. He reshuffled the cards and dealt 30 cards. This time, the number of red cards exceeded the number of black cards by 10. Determine which deal is closer to the ...
*Thursday, April 9, 2015 by Scott*

**calculus (please with steps and explanations)**

consider the function f that is continuous on the interval [-5,5] and for which the definite integral 0(bottom of integral sign) to 5(top of integral sign) of f(x)dx=4. Use the properties of the definite integral to evaluate each integral: (a) definite integral from 0(on the ...
*Thursday, April 9, 2015 by Linda*

**Calculus**

The sun is setting at the rate of 1/4 deg/min, and appears to be dropping perpendicular to the horizon, as depicted in figure 6.2.5. How fast is the shadow of a 25 meter wall lengthening at the moment when the shadow is 50 meters long?
*Thursday, April 9, 2015 by John*

**calculus**

karen hits a tennis ball with an initial velocity of 42 feet per second an at angle of 16 degree with the horizontal from a height of 2 feet. she is 20 feet from the net and the net is 3 feet. will the ball go over the net?
*Wednesday, April 8, 2015 by BK*

**calculus**

consider the function f that is continuous on the interval [-5,5] and for which the definite integral 0(bottom of integral sign) to 5(top of integral sign) of f(x)dx=4. Use the properties of the definite integral to evaluate each integral: (a) definite integral from 0(on the ...
*Wednesday, April 8, 2015 by Linda*

**calculus**

A conical drinking cup is made from a circular piece of paper of radius R inches by cutting out a sector and joining the edges CA and CB. Find the radius, height and volume of the cone of greatest volume that can be made this way
*Wednesday, April 8, 2015 by Linda*

**Calculus**

A hot air balloon is 150 ft above the ground when a motorcycle passes beneath it (traveling in a striaght line on a horizontal road) going 58 ft/sec. If the balloon is rising vertically at a rate of 10 ft/sec, what is the rate of change of the distance between the motorcycle ...
*Wednesday, April 8, 2015 by Linda*

**calculus **

A conical drinking cup is made from a circular piece of paper of radius R inches by cutting out a sector and joining the edges CA and CB. Find the radius, height and volume of the cone of greatest volume that can be made this way.
*Wednesday, April 8, 2015 by Linda*

**Calculus (urgent help)**

consider the function f that is continuous on the interval [-5,5] and for which the definite integral 0(bottom of integral sign) to 5(top of integral sign) of f(x)dx=4. Use the properties of the definite integral to evaluate each integral: (a) definite integral from 0(on the ...
*Wednesday, April 8, 2015 by Linda*

**calculus**

A box with a square base is to be constructed with a surface area of 726 square centimeters. 1. Draw a diagram of the box. Label the diagram appropriately with variables. 2. Write an objective equation and a constraint equation (label each one as objective or constraint). 3. ...
*Wednesday, April 8, 2015 by Courtney*

**PRE - CALCULUS**

Solve the quadratic equation by the square root property. (2x + 5)2 = 49 A. {-6, 1} B. {0, 1} C. {-27, 27} D. {1, 6} d?
*Wednesday, April 8, 2015 by Ciara*

**PRE - CALCULUS**

Evaluate the radical expressions or indicate that the root is not a real number. 3sqrt-4^3 A. -64 B. 4 C. -4 D. not a real number B?
*Wednesday, April 8, 2015 by Ciara*

**Calculus**

When production is 1700, marginal revenue is 8 dollars per unit and marginal cost is 6.75 dollars per unit. Do you expect maximum profit to occur at a production level above or below 1700? If production is increased by 50 units, what would you estimate the change in profit ...
*Tuesday, April 7, 2015 by Nope*

**Calculus**

A wire 7 meters long is cut into two pieces. One piece is bent into a square for a frame for a stained glass ornament, while the other piece is bent into a circle for a TV antenna. To reduce storage space, where should the wire be cut to minimize the total area of both ...
*Tuesday, April 7, 2015 by Nope*

**calculus**

Solve the equation. Give the exact solution. 2*10^(5x-3)+5=17
*Tuesday, April 7, 2015 by Michael J*

**calculus**

Find the area under one arch of curve y=cos(x/4). This lesson is plane areas in rectangular coordinates. I don't know how to solve it. Thanks for your help.
*Tuesday, April 7, 2015 by Jhun*

**Calculus**

Evaluate dy/dt for 2xy-2x+2y^3=-10 with the conditions dx/dt=-4 x=2 y=-1 dy/dt=?
*Monday, April 6, 2015 by Frankzilla*

**Calculus**

Cost: C^2=x^2+98*sq rt of x + 57 Revenue:890(x-4)^2+29R^2=26,100 Find the marginal cost dC/dx at x=4
*Monday, April 6, 2015 by Frankzilla*

**Calculus**

Find the rate of change of total revenue, cost, and profit with respect to time. Assume that R9x) and C9x) are in dollars. R(x)=60x-0.5x^2 C(x)=5x+15 x=30 and dx/dt=20 units per day
*Monday, April 6, 2015 by Billy the Goat*

**Calculus**

a 14 foot ladder is leaning against a building. If the bottom of the ladder is sliding along the pavement directly away from the building at 3 feet/second, how fast is the top of the ladder moving down when the foor of the ladder is 5 feet from the wall? I got -1.083 when I ...
*Monday, April 6, 2015 by Billy the Goat*

**Calculus**

a 12 foot ladder is leaning against a building. If the bottom of the ladder is sliding along the pavement directly away from the building at 1 feet/second, how fast is the top of the ladder moving down when the foor of the ladder is 2 feet from the wall?
*Monday, April 6, 2015 by Billy the Goat*

**Pre-Calculus**

Convert from standard to vertex form: (x+5)(x+4) x^2+ 9x + 20 (x+3)^2 + 20 - 9 (x+3)^2 + 11 <------
*Monday, April 6, 2015 by Lucina*

**Calculus **

Let f(x)=(lnx)^4 f'(x)=4(ln(x))^3/x what is f'(e^2)=?
*Monday, April 6, 2015 by Dani*

**Calculus 2 (Series)**

Can anyone help me start this problem from beginning to end, along with explanations on how to go about the problem for a better understanding how to do this series problem? 1) Find the values of p for which the series is convergent. Summation notation symbol (with n=1 on ...
*Monday, April 6, 2015 by Sena*

**calculus**

A ball is thrown vertically upward with an initial velocity of 128 feet per second, the ball’s height after t second is s(t) = 128t – 16t². Find the instantaneous velocity at 4 seconds.
*Monday, April 6, 2015 by syu*

**calculus**

A ball is thrown from an initial height of 130 feet with an initial upward velocity of 35ft/s . The ball's height H (in feet) after T seconds is given by the following h=130-6t-16t^2
*Monday, April 6, 2015 by juan*

**Calculus**

1. integral (x^3 * sqrt(x^2-4)) dx I'm confused on how to start this problem, if I am doing trig substitution.
*Sunday, April 5, 2015 by K*

**pre calculus**

the downhill ski club is organizing a ski trip. group tickets for the ski trip are priced at 20 for the first 100 skiers and a discount of 5.00 for each of the skiers over 100. a) write a formula to find the average cost of x skiers. b)write a formula to find the average cost ...
*Friday, April 3, 2015 by syed*

**pre calculus**

the downhill ski club is organizing a ski trip. group tickets for the ski trip are priced at 20 for the first 100 skiers and a discount of 5.00 for each of the skiers over 100. a) write a formula to find the average cost of x skiers. b)write a formula to find the average cost ...
*Friday, April 3, 2015 by syed*

**Calculus**

List x1, x2, x3, x4 where xi is the right endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 3 and x = 5. 3, 3.5, 4, 4.5 3, 3.2, 4.6, 5 3.5, 4, 4.5, 5 3.25, 3.75, 4.25, 4.75 my answer was a because i kept getting numbers like 3, ...
*Friday, April 3, 2015 by bob*

**calculus**

A rectangular area is to be enclosed and divided into thirds. The family has $400 to spend for the fencing material. The outside fence costs $10 per running foot installed, and the dividers cost $20 per running foot installed. What are the dimensions that will maximize the ...
*Friday, April 3, 2015 by Anonymous*

**Math/Calculus**

Solve the differential equation y'=3t^2+4. Solve the initial value problem y(0)=3. Separation of variables! My work: dy/dt= 3t^2+4 dy= 3t^2+4 dt Then you integrate both sides. ∫ dy= ∫ 3t^2+4dt Question: is there a 1 in dy? ( ∫ 1dy)? If so: y+C1=t^3+4t+C2 ...
*Thursday, April 2, 2015 by Sarah*

**calculus**

A closed cylindrical can is to hold 2 litter (200 cm³) of liquid. How should we choose the height and radius to minimize the amount of material needed to manufacture the can?
*Thursday, April 2, 2015 by nani*

**Calculus**

Use implicit differentiation to differentiate y=x^(8/37), by writing it as y^37=x^8. Express your answer only in terms of x.
*Thursday, April 2, 2015 by Anonymous*

**Calculus**

If two resistors with resistances R1 and R2 are connected in parallel, as in the figure, then the total resistance R, measured in Ohms (Ω), is given by: 1/R=1/R1+1/R2 If R1 and R2 are increasing at rates of .3Ω/s and .2Ω/s, respectively, how fast is R increasing...
*Wednesday, April 1, 2015 by Jen*

**Calculus**

1 pt) For positive constants k and g, the velocity, v, of a particle of mass m at time t is given by v=mg/k(1−e−kt/m). At what rate is the velocity is changing at time 0? At t=8? What do your answers tell you about the motion? At what rate is the velocity changing ...
*Wednesday, April 1, 2015 by Jen*

**calculus**

(1 pt) When air expands adiabatically (without gaining or losing heat), its pressure P and volume V are related by the equation PV1.4=C where C is a constant. Suppose that at a certain instant the volume is 390 cm3, and the pressure is 75 kPa (kPa = kiloPascals) and is ...
*Wednesday, April 1, 2015 by emily*

**calculus**

1 pt) Coroners estimate time of death using the rule of thumb that a body cools about 2 degrees F during the first hour after death and about 1 degree F for each additional hour. Assuming an air temperature of 68 degrees F and a living body temperature of 98.6 degrees F, the ...
*Wednesday, April 1, 2015 by emily*

**calculus**

Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 7.5 mi2/hr. How rapidly is radius of the spill increasing when the area is 10 mi^2?
*Wednesday, April 1, 2015 by Anonymous*

**Calculus **

Use implicit differentiation to differentiate y=x8/37, by writing it as y37=x8. Express your answer only in terms of x.
*Wednesday, April 1, 2015 by Anonymous*

**calculus**

A painting is hung on a wall in such a way that its upper and lower edges are 10 ft and 7ft above the floor, respectively. An observer whose eyes are 5 ft above the floor stands x feet from the wall. How far away should the observer stand to maximize the angle subtended by the...
*Wednesday, April 1, 2015 by Linda*

**calculus**

The operating cost, C, in dollars per hour, for an airplane cruising at a height of h metres and an air speed of 200km/h is given by: C = 4000 + h/15 + 15000000/h for the domain 1000 ≤ h ≤ 20000. Determine the height at which the operating cost is at a minimum, and...
*Tuesday, March 31, 2015 by sierra*

**Calculus 1**

How do you find the derivative of 1/3(x^2+2)^3/2 ? Please help
*Tuesday, March 31, 2015 by Danny*

**calculus**

cos2x=secx find x
*Tuesday, March 31, 2015 by Cody*

**Calculus **

A certain magical substance that is used to make solid magical spheres costs $800 per cubic foot. The power of a magical sphere depends on its surface area, and a magical sphere can be sold for $20 per square foot of surface area. If you are manufacturing such a sphere, what ...
*Monday, March 30, 2015 by Anonymous*

**Calculus study**

A baseball team plays in a stadium that holds 52000 spectators. With the ticket price at $9 the average attendance has been 21000. When the price dropped to $6, the average attendance rose to 26000. a) Find the demand function p(x), where x is the number of the spectators. (...
*Monday, March 30, 2015 by Juan *

**Calculus**

A small resort is situated on an island that lies exactly 5 miles from P, the nearest point to the island along a perfectly straight shoreline. 10 miles down the shoreline from P is the closest source of fresh water. If it costs 1.5 times as much money to lay pipe in the ...
*Monday, March 30, 2015 by Emily*

**calculus**

Find the point on the line 2x+4y+7=0 which is closest to the point (4,−3).
*Monday, March 30, 2015 by Emily*