Sunday

October 4, 2015
**Calculus**

Use linear approximation to approximate f(0.8) given f(x)=2x^3-3x+1
*Sunday, December 14, 2014 by Anonymous*

**AP Calculus**

The management of a large store has 1600 feet of fencing to fence in a rectangular storage yard using the building as one side of the yard. If the fencing is used for the remaining 3 sides, find the area of the largest yard possible.
*Sunday, December 14, 2014 by Sarah*

**Calculus**

Find the x-values where f(x)=x^4-8x^3 attains a relative minimum, relative maximum, and inflection points, if any. Justify your answers. My derivative test didn't seem right.
*Sunday, December 14, 2014 by Anonymous*

**Calculus**

Show that Rolle's Theorem applies to the given function for ht eg oven values of x: x=-1 and x=4 for f(x)=3x-x^2+2
*Sunday, December 14, 2014 by Anonymous*

**Calculus**

A baseball diamond is a square with side 90 ft. a batter hits the ball and runs toward first base with a speed of 24 ft/s. (a) At what rate is his distance from second base decreasing when he is halfway to first base? Is the answer 0.0932ft/s? I don't see that it is ...
*Sunday, December 14, 2014 by Anonymous*

**Calculus**

A boat is pulled into a dock by a rope attached to the bow of the boat and passing through a pulley on the dock that is 1 m higher than the bow of the boat. If the rope is pulled in at a rate of 1m/s,how fast is the boat approaching the dock when it is 8 m from the dock?
*Sunday, December 14, 2014 by Anonymous*

**Calculus**

A baseball diamond is a square with side 90 ft. a batter hits the ball and runs toward first base with a speed of 24 ft/s. (a) At what rate is his distance from second base decreasing when he is halfway to first base? (b) At what rate is his distance from third base increasing...
*Sunday, December 14, 2014 by Anonymous*

**Calculus**

A baseball diamond is a square with side 90 ft. a batter hits the ball and runs toward first base with a speed of 24 ft/s. (a) At what rate is his distance from second base decreasing when he is halfway to first base? (b) At what rate is his distance from third base increasing...
*Sunday, December 14, 2014 by Anonymous*

**calculus**

The graph of a function f is shown. Use the differential equation and the given point to find an equation of the function. dy/dx=4x+(9x^2/(3x^3+1)^(3/2)) and the point (0,2) using the substitution method of integration.
*Sunday, December 14, 2014 by JT*

**Calculus 1**

A woman at a point A on the shore of a circular lake with radius r=4 wants to arrive at the point C diametrically opposite A on the other side of the lake in the shortest possible time. She can walk at the rate of 10mph and row a boat at 5mph. What is the shortest amount of ...
*Saturday, December 13, 2014 by Rainbows*

**Calculus**

Find the length of the entire perimeter of the region inside r=15sin(theta) but outside r=1. I am not sure how to start the problem
*Friday, December 12, 2014 by Susan*

**Calculus **

My question: An equation of the line tangent to the graph of f(x) = x(1 - 2x)3 at the point (1, –1) is?? My answer: y = –2x + 1
*Thursday, December 11, 2014 by Jenny*

**Math-Calculus**

Find the point on the line -2x + 4y + 3 =0 which is closest to the point (-2,1). Note: I have been struggling on this for hours!
*Thursday, December 11, 2014 by Jacob*

**calculus**

after t seconds the position of a particle which is moving along a straight line is x=2t^3-9t^2+12t+6, when is the acceleration zero? determine the velocity at that time.
*Thursday, December 11, 2014 by khai*

**Calculus**

Hi! I need help with this problem: For 0(smaller or equal to) t (smaller or equal to) 9, a particle moves along the x-axis. The velocity of the particle is given by v(t)= (sin pi/4 t). The particle is at position x= -4 when t=0. a) For 0 (smaller or equal to) t (smaller or ...
*Thursday, December 11, 2014 by Dana*

**calculus **

lim(x tends to 3) (square root(x^2+7) -4) divided by (square root(x^2-8) -1) Pls help and list the steps. Thx
*Wednesday, December 10, 2014 by ivan*

**Calculus**

If the y-coordinate at each point of inflection on the curve y=e^(-x^2) is 1/e^a, then a = ?
*Wednesday, December 10, 2014 by JOE*

**Calculus**

This is a calculus homework question but in reality the problem here is understanding the algebra. Find the Critical Numbers of f(x) = x^(3/5)(4-x) The product rule gives -x^(3/5) + (12-3x)/(5x^(2/5) My booklet explains that simplifying this gives you 12-8x / (5x^(2/5). How ...
*Wednesday, December 10, 2014 by David*

**College Algebra**

According to Newton's law of cooling, the rate at which an object cools is directly proportional to the difference in temperature between the object and the surrounding medium. The face of a household iron cools from 130° to 100° in 30 minutes in a room that ...
*Wednesday, December 10, 2014 by Kyle *

**Calculus**

A deposit of $5,000 at 4% interest compounded continuously will grow to V(t) = 5000e^0.04t dollars after t years. Find the average value during the first 20 years (that is, from time 0 to time 20). (Round your answer to the nearest cent.)
*Wednesday, December 10, 2014 by Madison*

**calculus**

The position, in feet, of a target is given by s(t)=250-3t+9t^2+2t^3, where t is the time in seconds. The origin of coordinates is at the point where an observer stands, and the positive direction of movement is that one pointing EAST from the origin. What is the initial ...
*Tuesday, December 9, 2014 by Jane*

**Calculus angle of elevation**

A man is walking towards a wall at 3 ft/sec while looking at a picture on the wall, at a height of 5 feet from the floor. How is the angle of observation changing when the man is 8 feet away from the screen.
*Tuesday, December 9, 2014 by Jane*

**Calculus- Tangent Line**

What is the slope of the tangent line to the curve at the point (4, 0)? Okay, so I got 0.5, did I do this right?
*Tuesday, December 9, 2014 by Harry*

**Euler's method help in Calculus?????**

Let dy/dx=xy . Use Euler's method with step size of 0.5 and the initial condition of y(0) = 3 to estimate y(2). I really am not sure if I did this right, but I got 3.4568 for y(2). I actually feel like it is wrong.
*Tuesday, December 9, 2014 by Jane*

**Calculus**

Y=2sinx-cos^2(x) F"(x)=-sinx+cos^2-sin^2(x) Find the points of inflection and concavities
*Tuesday, December 9, 2014 by Anonymous*

**Calculus**

Find the equation of the tangent line to the hyperbola 3x^2-4y^2=8 which is/are perpendicular to the line 2x-3y+6=0. Give the answers in general form.
*Tuesday, December 9, 2014 by Diolo*

**Calculus**

lim (e^x+3x)^1/x as x approaches 0
*Tuesday, December 9, 2014 by Diolo*

**Calculus**

Y=2sinx-cos^2(x) on [0, 2pi] How do you solve for the x-intercept
*Tuesday, December 9, 2014 by Anonymous*

**General Calculus Question**

How do you solve a limit when it approaches infinity and there is a square root in the denominator? say the highest power is x^2 in both the numerator and denominator.
*Monday, December 8, 2014 by Anonymous*

**AP Calculus**

For the function y=4-2x^2+1/6x^4 find the following: Domain x and y intercepts Vertical asymptotes Horizontal asymptotes Symmetry F'(x) Critical numbers Increasing f(x) Decreasing f(x) Extrema F"(x) Possible points of inflection Concave up Concave down Points of ...
*Monday, December 8, 2014 by Sarah*

**Calculus**

A particle moves along line segments from the origin to the points (3, 0, 0), (3, 3, 1), (0, 3, 1), and back to the origin under the influence of the force field F(x, y, z) = z2i + 5xyj + 4y2k. I have tried multiple times to solve this problem but the answer is still not right.
*Monday, December 8, 2014 by Katie*

**Calculus**

Find critical points for y'=2/3x^3-4x
*Monday, December 8, 2014 by Anon*

**Calculus **

A particle moves along line segments from the origin to the points (3, 0, 0), (3, 3, 1), (0, 3, 1), and back to the origin under the influence of the force field F(x, y, z) = z2i + 5xyj + 4y2k. I have tried multiple times to solve this problem but the answer is still not right.
*Monday, December 8, 2014 by Jessica*

**Calculus**

So this one is confusing me: limit of n as it approaches infinity of (n{SIGMA}i=1) (1/(2^i) *the n is on top of the sigma notation and i=1 is at the bottom. I understand that 'i' would equal (n(n+1))/2 however the algebra from there confuses me.
*Monday, December 8, 2014 by David*

**calculus**

A rectangular fence has to be built from both wood and metal so that opposite parallel sides of the fence are made from the same type of material. The wood costs $10 per foot and the metal costs $20 per foot of the fence used. If you only have $400 to spend on material, what ...
*Monday, December 8, 2014 by Paige *

**Calculus**

I am trying to solve the following L'hopital's limits question below: lim x -> 0 from the positive direction of ( 5^(sin(x)) - 1 )/ (x)
*Monday, December 8, 2014 by David*

**calculus**

Previously asked: the length of a rectangular prism is increasing at a rate of 8 cm/s, its width is increasing at a rate of 3 cm/s, and its height is increasing at a rate of 5 cm/s. when the length is 20 cm, width is 10 cm, and height is 15 cm, how fast is the volume of the ...
*Sunday, December 7, 2014 by Dani*

**calculus**

First, the bond pays 96 + 7 t per year for 10 years. Second, the interest rate is 5.25% compounded continuously. Round your answer to the nearest cent. Find the present value?
*Sunday, December 7, 2014 by Dat nguyen*

**Calculus**

Find the area of the region bounded by the curves y=12-x^2 and y=x^2-6. Hint:The answer should be a whole number.
*Sunday, December 7, 2014 by Bill*

**Calculus**

L'hopital's question below: lim x -> 0 from the positive direction of ( 5^(sin(x)) - 1 )/ (x)
*Sunday, December 7, 2014 by David*

**Math - Calculus**

If 75100 dollars is deposited in an account for 13 years at 5.35 percent compounded continuously , find the average value of the account during the 13 years period. The average value in the account is ? ** im alittle confused in how to find the average value please help and ...
*Sunday, December 7, 2014 by Anonymous*

**Calculus**

Find the average value of the function f(x) 8x^2-9x+8 on the interval [3,5]. Find the value of the x-coordinate at which the function assumes it's average value The average value is ? the x-coordinate is ? Please help and showing work is much appreciated. Thank you
*Sunday, December 7, 2014 by Anonymous*

**Calculus**

Lines tangent to the curve y-1=2x^2+3x pass through the point A(2,-1). Find the x-coordinate(s) of the point(s) of tangency. The answer is 2+2^1/2, 2-2^1/2, I just don't know how to get there. Please help! Thank you!
*Sunday, December 7, 2014 by Ty*

**Pre calculus**

at an archaeological site remains of plant material will found to have 28.9% of the amount of carbon-14 in a living sample. What was the approximate age of the plant material?
*Saturday, December 6, 2014 by crisly*

**calculus**

the length of a rectangular prism is increasing at a rate of 8 cm/s, its width is increasing at a rate of 3 cm/s, and its height is increasing at a rate of 5 cm/s. when the length is 20 cm, width is 10 cm, and height is 15 cm, how fast is the volume of the rectangular prism ...
*Saturday, December 6, 2014 by Dani*

**calculus**

definite integral of (e^(8x))cosh(8x)dx from 0 to 1/16 -I substitued the definition of cosh in, i.e. (e^(8x) + e^(-8x)/2 but i cant get the "e's" to combine and i know the answer is e/32
*Saturday, December 6, 2014 by gregory*

**Pre Calculus**

You have been hired by the Humane Society to construct six 2 by 3 animal cages using 1400 feet of chain fence. Express the length and width using function notation. Include a graph with the area function with explanation of significance. Find the dimensions that maximize the ...
*Friday, December 5, 2014 by Guillermo*

**Calculus**

Find the interval on which f(x)=xe^-x is increasing. I got (1,infinity)..
*Friday, December 5, 2014 by Anonymous*

**Calculus**

On what intervals is the function f(x)=e^e^2 increasing? Concave upward?
*Friday, December 5, 2014 by Anonymous*

**calculus Please Help**

The cost for a toy company to produce x Cosmic Starships is C(x) = 1400 + 6x − 0.01x2. What ￼￼￼￼￼￼￼￼￼￼is the marginal average cost function? Can someone please explain how to do this to I...
*Friday, December 5, 2014 by Erica*

**Calculus**

Differentiate. cos^-1 2x
*Friday, December 5, 2014 by Anonymous*

**Calculus**

Differentiate. cos^3x My answer: -3cos^2x sin^2x
*Friday, December 5, 2014 by Anonymous*

**Calculus**

Find the interval on which f(x)=xe^-x is increasing. I got (1,infinity)..
*Friday, December 5, 2014 by Anonymous*

**Calculus**

If f(x)=the sqrt of 3x,find f'(3). Isn't it 3/2•sqrt of 3?
*Friday, December 5, 2014 by Anonymous*

**Calculus Please Help**

Can you please explain these two questions to me? Suppose the population size of a predator is given by P (x) = 0.006x2 + 0.005x, where x represents the population of its prey. If the population of the prey is 10,000 at the first of January and is reduced to 6,000 by May 1 of ...
*Friday, December 5, 2014 by Eric*

**Calculus**

How do I find the area of the region bounded by the graphs of the given equations? y=x+20; y=x^2
*Friday, December 5, 2014 by Duane*

**Calculus question please explain**

I know the answer to the first one is "e" and the answer to the second one is "a "but I have no idea why please explain how to do these two problems. I am very confused with this method. Thank you! The “Cobb-Douglas” productivity function for a ...
*Friday, December 5, 2014 by Jennifer *

**calculus**

If sec x = -3, 0 < x < pi, find cot x.
*Thursday, December 4, 2014 by Grant*

**pre-calculus**

6cos^2(x)-5cos(x)-6
*Thursday, December 4, 2014 by Ashleigh*

**Calculus**

can you show me the steps to evaluate this indefinite integral. s(e/x^4+pie^2/square root of x
*Thursday, December 4, 2014 by Duane*

**Calculus**

The marginal profit in dollars on Brie cheese sold at a cheese store is given by P'(x)=x(60x^2+30x), where x is the amount of cheese sold in hundreds of pounds. The "profit" is -$50 when cheese is sold. a. Find the profit function. P(x)= b. Find the profit from ...
*Thursday, December 4, 2014 by Duane*

**Calculus**

a particle moves along the x-axis at a velocity of v(t)=1 sqrt(t), t>0. at time t=1 , its position is x=4. find the acceleration and position functions for the particle
*Thursday, December 4, 2014 by Steph*

**Calculus**

A sherman is in a rowboat on a lake and 3 km from shore. He wishes to reach a store 2 km down the (straight) shore. He can row at 5 km/h and run at 13 km/h. To what point down-shore should he row to get to the store as quickly as possible? 8. The cross-section of a tunnel
*Wednesday, December 3, 2014 by Lucy*

**Calculus **

With the following coordinates (16,46) (18,64) (20,60) create three formulas using Y+Ax^2+Bx+C then solve for A,B, and C to form the final equation.
*Wednesday, December 3, 2014 by Hailey*

**CALCULUS - PLEASE HELP!**

It is known that homing pigeons tend to avoid flying over the water in the daytime, perhaps because the downdrafts of air over water make flying difficult. Suppose a homing pigeon is released on an island at point C , which is 3 km directly out in the water from a point B ...
*Tuesday, December 2, 2014 by Mary*

**calculus 2**

Find all points of intersection of the given curves. (Assume 0 ≤ θ ≤ 2π. Order your answers from smallest to largest θ. If an intersection occurs at the pole, enter POLE in the first answer blank.) r = 1 − cos θ, r = 1 + sin θ
*Tuesday, December 2, 2014 by Linda*

**Calculus**

Differentiate. e^cos(x^2+1) Is the answer -2xe^cos(x^2+1) sin(x^2+1)?
*Monday, December 1, 2014 by Anonymous*

**calculus**

Let f'(x)=4x^3-12x^2. (a) find three different functions with derivative equal to f'(x). how are the graphs of the three functions related? the only one that i can figure out is: f(x)=x^4+4x^3+y where y can equal any constant. any help on figuring out the other two ...
*Monday, December 1, 2014 by kailee*

**calculus**

When a ball is thrown vertically upward into the air with a velocity of 79 ft/sec its height, y(t), in feet after t seconds is given by y(t) = 79t − 16t 2 . Find the average velocity of the ball over the interval from 3 to 3 + h seconds, h 6=/= 0. 1. average vel. = &#...
*Monday, December 1, 2014 by Morgan*

**calculus**

I needed help with these FRQ in my APCalc course. Any help or walkthrough would be extremely helpful - thanks in advance. Let f be the function given by f(x)=3ln((x^2)+2)-2x with the domain [-2,4]. (a) Find the coordinate of each relative maximum point and each relative ...
*Monday, December 1, 2014 by emily*

**General Calculus Question**

On a graph what ways can it not be differentiable? I know at cusps it's not differentiable but are there other instances where it is not differentiable?
*Monday, December 1, 2014 by Anonymous*

**Calculus**

Water is being poured into a spherical bowl of radius 4cm at a rate of 2cm3/s. How fast is the water level rising when it is at 2cm?
*Monday, December 1, 2014 by Sam*

**calculus, help!**

Evaluate the definite integral: int_{1}^{e^9} \frac{dx}{x \sqrt{\ln x}} = i gt my answer as 1^(e^9) but it's saying it's wrong
*Monday, December 1, 2014 by Amber *

**Calculus**

consider the function f(x) = (x if x<1 (1/x if x>or equal to 1 Evaluate the definite integral: int_{-2}^{3} f(x)\,dx =
*Monday, December 1, 2014 by Amber *

**Calculus**

Which of the following functions does not have a derivative of zero? A. y=-1/100 B. y=4(pi)^2-9 C. y=sin^2x+cos^2x D. y=cscxtanxcosx E. All do
*Monday, December 1, 2014 by Anonymous*

**Calculus**

Estimate the area under the graph of f(x)= x^2 + 2 x from x=1 to x=5 using 4 approximating rectangles and left endpoints.
*Monday, December 1, 2014 by Kate*

**Calculus...help**

The projected public spending by the British government for the years 2010-2011 (t = 0) through 2014-2015 (t = 4) is 692 billion pounds/year. The projected public revenue for the same period is f(t) = 292.6t + 134.4 / t + 6.9 + 500 billion pounds (0 ge t ge 4). Find the ...
*Monday, December 1, 2014 by sarah*

**calculus**

The number of U.S. citizens 65 and older from 1990 through 2050 is estimated to be growing at the rate of, R(t)=0.063t^2 -0.48t+3.87, (0 less than or = t less than or = 15) million people/decade, where t is measured in decades and t = 0 corresponds to 1900. Show that the ...
*Sunday, November 30, 2014 by mar*

**Differential equations in Calculus...plsssss help?**

Suppose that represents the temperature of a cup of coffee set out in a room, where T is expressed in degrees Fahrenheit and t in minutes. A physical principle known as Newton’s Law of Cooling tells us that dT/dt = -1/15T+5 15T + 5. a) Supposes that T(0) = 105. What does ...
*Sunday, November 30, 2014 by Bridget*

**Calculus**

Find the limit as x approaches 1 5/(x-1)^2 I don't understand how to solve it because there would be a 0 on the denominator.
*Sunday, November 30, 2014 by Anonymous*

**Calculus**

Find dy/dx if x^2+y^2=2xy A. x/(x-y) B. (y+x)/(y-x) C. 1 D. -x/y E. None of these
*Sunday, November 30, 2014 by Anon*

**Calculus with Diffrential Equations: Pleease help?**

Suppose that represents the temperature of a cup of coffee set out in a room, where T is expressed in degrees Fahrenheit and t in minutes. A physical principle known as Newton’s Law of Cooling tells us that dT/dt = -1/15T+5 15T + 5. a) Supposes that T(0) = 105. What does ...
*Sunday, November 30, 2014 by Bridget*

**Calculus**

Suppose that represents the temperature of a cup of coffee set out in a room, where T is expressed in degrees Fahrenheit and t in minutes. A physical principle known as Newton’s Law of Cooling tells us that dT/dt = -1/15T+5 15T + 5. a) Supposes that T(0) = 105. What does ...
*Sunday, November 30, 2014 by Bridget*

**Help with differential eqs problem???? (Calculus)**

Consider the differential equation dy/dt=y-t a) Determine whether the following functions are solutions to the given differential equation. y(t) = t + 1 + 2e^t y(t) = t + 1 y(t) = t + 2 b) When you weigh bananas in a scale at the grocery store, the height h of the bananas is ...
*Sunday, November 30, 2014 by Stacey*

**Calculus**

The slope of the line tangent to the curve xy+(y+1)^2=6 at the point (2, 1) is
*Sunday, November 30, 2014 by James*

**AP Calculus **

For which of these functions f(x) does limit as x approaches negative infinity f(x)=2 A. (x-2)/(3x-5) B. 2x/sqrt(x-2) C. (2x^2-6x+1)/(1+x^2) D. (2x-1)/(x^2+1) E. None of these
*Sunday, November 30, 2014 by Sarah*

**Calculus**

Find limit as x approaches 5 (x^2-3x-10)/(x-5)
*Sunday, November 30, 2014 by Anonymous*

**AP Calculus**

Find the derivative for f(x)=-x^2+x Do I put -x^2 on the denominator? How would I solve it if that's the case?
*Sunday, November 30, 2014 by Sarah*

**Calculus**

Find limit as x approaches -1 (x^2+2x+3)/(x^2+1) A. 0 B. 1 C. Infinity D. DNE E. None of these
*Sunday, November 30, 2014 by Anonymous*

**AP Calculus**

Find f'(x): f(x)=(x^2-3x)/x^2 A. 2x-3/x^2 B. 2x-3/2x C. 1-(3/x) D. 3/x^2 E. None of these I get confused on the simplifying part.
*Sunday, November 30, 2014 by Anon*

**AB Calculus**

I figured out that part "A" is -3/8, but i can't figure out part 2, a or b. please explain and help. thanks. Sand is falling from a rectangular box container whose base measures 40 inches by 20 inches at a constant rate of 300 cubic inches per minute. a) how is ...
*Sunday, November 30, 2014 by Jake*

**AP Calculus**

Find limit as x approaches 1 5/(x-1)^2 A. 0 B. Negative infinity C. 5/4 D. Infinity E. None of these
*Sunday, November 30, 2014 by Anon*

**Calculus**

Find the derivative: f(x)=1/cubed root(3-x^3) A. -1/3(3-x^3)^4/3 B. x^2/(3-x^3)^4/3 C. -x^2/(3-x^3)^2/3 D. -x^2/(3-x^3)^4/3 E. None of these
*Sunday, November 30, 2014 by Anonymous*

**Calculus**

If f(x)=x^2+1 and g(x)=2x-1, find d/dx[f'(g(x))] at x=1 A. 2 B. 6 C. 4 D. 0 E. None of these
*Sunday, November 30, 2014 by Anon*

**AP Calculus**

Find all points on the graph of f(x)=-x^3+3x^2-2 where there is a horizontal tangent line.
*Sunday, November 30, 2014 by Sarah*

**Calculus**

Find the limit as x approaches 0 [(sqrt(x+9))-3]/x A. 0 B. 1 C. Infinity D. 1/3 E. None of these
*Sunday, November 30, 2014 by Anonymous*

**Calculus,Reaction rates**

A man walks across a bridge at the rate of 5 ft/s as a boat passes directly beneath him at 10 ft/s. If the bridge is 10 ft above the boat, how fast are the man and the boat separating 1 second later?
*Sunday, November 30, 2014 by ray*

**AP Calculus**

Let f(7)=0, f'(7)=14, g(7)=1, g'(7)=1/7. Find h'(7) if h(x)=f(x)/g(x)
*Sunday, November 30, 2014 by Sarah*

**Calculus**

Find the derivative of x^2f(x) A. x[xf'(x)+2f(x)] B. 2xf'(x) C. x[xf'(x) +2f'(x)] D. x^2f'(x) E. None of these
*Sunday, November 30, 2014 by Anonymous*

**Calculus,reaction rates**

A car starting at 12:00 noon travels west at a speed of 30 kph. Another car starting from the same point at 2:00 PM travels north at 45 kph. Find how fast the two are separating at 4:00 PM?
*Sunday, November 30, 2014 by @jayr*