Tuesday

April 21, 2015

April 21, 2015

**Calculus **

Compute the absolute and relative errors in using c to approximate x. x=e;c=2.68
*Sunday, June 1, 2014 at 10:47pm*

**Pre-Calculus**

if cos theta =7/13, where 0<theta<pi/2, fin the value of cos2theta
*Saturday, May 31, 2014 at 6:56pm*

**calculus**

Identify the open intervals) where the function f of F(x)= x√10-x^2 is increasing.
*Wednesday, May 28, 2014 at 2:21pm*

**calculus**

A golf ball is hit off the top of a cliff that is 75 feet tall at an angle of 45° to the horizontal with an initial velocity of 80 feet per second. The quadratic equation shown below models the height, h(x), of the ball when it is x feet from the cliff’s edge. How far...
*Wednesday, May 28, 2014 at 12:14pm*

**Calculus**

Find all values for c in the intercal (1,4) so that the slope of the tangent line at (c,f(c)) equals the slope of the secant line through (1,1/3) and (4,2/3) where f(x) = x/(x+2) 1 </ x </ 4 (<-- that is suppose to be the less than or equal to sign) I'm not sure ...
*Tuesday, May 27, 2014 at 11:21pm*

**Calculus**

Please help I am stuck evaluate the following intergral x cos 15x dx.
*Tuesday, May 27, 2014 at 11:17pm*

**calculus**

Evaluate the following integrals using the given substitutions. (a) (3x^2 + 10x)dx/(x^3 + 5x^2 + 18 , substitution u = x3 + 5x2 + 18; (b)(14x + 4)cos(7x^2 + 4x)dx,substitution u = 7x^2 + 4x.
*Tuesday, May 27, 2014 at 4:37pm*

**Calculus**

Let t be some ﬁxed real number. Find the volume of the region bounded by y =1/x and the y = 0 on the interval [1, t] rotated about the x-axis. What happens as t → ∞?
*Tuesday, May 27, 2014 at 3:10pm*

**Calculus**

inding vertex and focus of parabola y^2 +4y +8x - 12 =0
*Tuesday, May 27, 2014 at 2:21pm*

**Calculus**

How do you solve the equation log(x+6)-log(2x+1)=log4
*Monday, May 26, 2014 at 2:06pm*

**Calculus**

A cable is suspended from two towers with a distance of 100m between them. The 1st tower has a height of 50m and the 2nd tower has a height of 70m from the ground. The lowest part of the cable has a distance of 47m from the ground. Find the length of the cable
*Sunday, May 25, 2014 at 4:37am*

**calculus**

A region is bounded in the second quadrant by the curve y = ln(1–x), the line y=3, and the y-axis. Find the area of the region.
*Thursday, May 22, 2014 at 6:50pm*

**college calculus**

the amount of carbon-14 in a mammoth's bone is 45% of the amount found in a living organism. How long ago did the mammoth die? the half-life of carbon-14 is about 5,730 years.
*Thursday, May 22, 2014 at 4:44pm*

**Calculus**

Jill burns 100 calories per hour while sleep and 300 calories per hour while walking and 200 calories per hour at work. If in a typical day Jill spends 7 hours sleeping, 2 hours walking and 6 hours working, what is her average calories burned for those hours? 166.67 cal/hr 200...
*Thursday, May 22, 2014 at 12:58pm*

**Calculus**

2x -------- (x-2)(x+2) using partial fractions That's supposed to be a division sign of some sort
*Thursday, May 22, 2014 at 5:33am*

**Calculus**

Consider the function f (x) = 2x^3 - 3x^2 - 72x + 7 Find and classify the critical points. Identify the intervals of increase and decrease, and state the intervals of concavity.
*Thursday, May 22, 2014 at 1:04am*

**Calculus**

find the co-ordinates y=x(2-x) where the gradient is 2
*Wednesday, May 21, 2014 at 1:23pm*

**Calculus**

1/X by first principles
*Wednesday, May 21, 2014 at 12:43pm*

**Calculus**

A fragment of bone is discovered to contain 20% of the usual carbon-14 concentration. Estimate the age of the bone to the nearest hundred years, given that Carbon-1 is radioactive with half-life of 5730 years and the rate of decay is given by the following differential ...
*Wednesday, May 21, 2014 at 2:20am*

**Calculus**

Find the volume of the solid generated by rotating about the y axis the area in the first quadrant bounded by the following curve and lines. y=x^2, x=0, y=2.
*Wednesday, May 21, 2014 at 2:17am*

**Calculus**

Find the area of the region enclosed by the parabolas y=x^2 and y+2x-x^2
*Wednesday, May 21, 2014 at 2:15am*

**Calculus**

2x -------- (x-2)(x+2) using partial fractions That's supposed to be a division sign of some sort
*Wednesday, May 21, 2014 at 2:14am*

**Calculus**

xe^x using integration by parts
*Wednesday, May 21, 2014 at 2:12am*

**Calculus**

x(x^2-1)^3 using change of variable
*Wednesday, May 21, 2014 at 2:09am*

**Calculus**

a rectangular storage area is to be constructed along the sides of a tall building. A security fence is required along the three remaining sides of the area. What is the maximum area that can be enclosed with 1000m fencing?
*Wednesday, May 21, 2014 at 12:21am*

**Calculus**

a meteorite slams into the earths crust and penetrates d=(1200t-36000t^2)m in t seconds after impact. What is the maximum depth of penetration?
*Wednesday, May 21, 2014 at 12:21am*

**Calculus **

An inverted conical tank is 3m tall and 1m in diameter at its widest point. The water is being pumped out of a spout 2m above the top of the tank. Recall that the density of water is ρ = 1000kg/m^3 (a) Find the work needed to empty the tank if it is full. Include units. (...
*Tuesday, May 20, 2014 at 11:28pm*

**Calculus **

I did an experiment where I had to measure how fast water flowed out of a container at different times and with different volumes (from 0mL-1000mL in increments of 50). I also had to record the values into a table and graph them. (I got an exponential function). I got a slope ...
*Tuesday, May 20, 2014 at 11:24pm*

**Calculus**

I have a data table and I graphed the data. I have to find the slope of a tangent at t=0. Would the slope just be zero?
*Tuesday, May 20, 2014 at 6:41pm*

**Calculus**

In First principles there is usually a part that states as lim approaches 0. Now I came across a question where the limit was as 1 approaches 3. what should I do?
*Tuesday, May 20, 2014 at 4:13pm*

**calculus**

Consider the motion of a particle of mass m falling vertically under the earth’s gravitational field, and suppose the downward motion is opposed by a frictional force p(v) dependent on the velocity v(t) of the particle. Then the velocity satisfies the equation mv0(t) = &#...
*Tuesday, May 20, 2014 at 2:59pm*

**Calculus**

A circular oilspill is spreading such that the radius is increasing at 0.5 metres per minute. Find the rate of increase of the are of the oil spill when the radius is 10m.
*Tuesday, May 20, 2014 at 1:22pm*

**Calculus**

a meteorite slams into the earths crust and penetrates d=(1200t-36000t^2)m in t seconds after impact. What is the maximum depth of penetration?
*Tuesday, May 20, 2014 at 1:13pm*

**Calculus**

a rectangular storage area is to be constructed along the sides of a tall building. A security fence is required along the three remaining sides of the area. What is the maximum area that can be enclosed with 1000m fencing?
*Tuesday, May 20, 2014 at 1:12pm*

**Calculus 1**

a rectangular storage area is to be constructed along the sides of a tall building. A security fence is required along the three remaining sides of the area. What is the maximum area that can be enclosed with 1000m fencing?
*Tuesday, May 20, 2014 at 12:26pm*

**Calculus**

Evaluate the integral of 4x^2(2+x^3)^9 dx. I'm supposed to use the substitution rule but I have absolutely no idea where to start with this problem.
*Tuesday, May 20, 2014 at 9:50am*

**Calculus**

I did an experiment where I had to measure how fast water flowed out of a container at different times and with different volumes. I also had to record the values into a table and graph them. (I got an exponential function). I am to answer the following questions and I do not ...
*Tuesday, May 20, 2014 at 2:56am*

**Calculus- answer check**

A brand new stock is also called an initial public offering. This model predicts the percent overvaluation of a stock as R(t)=9t((t-3)^3/2.718) where is the overvaluation in percent and t is the time in months after the initial issue. Use the information provided by the first ...
*Monday, May 19, 2014 at 10:50pm*

**Calculus **

An inverted conical tank is 3m tall and 1m in diameter at its widest point. The water is being pumped out of a spout 2m above the top of the tank. Recall that the density of water is = 1000kg/m^3 (a) Find the work needed to empty the tank if it is full. Include units. (b...
*Monday, May 19, 2014 at 10:10pm*

**Calculus**

Solve the differential equation dy/dx=3x^2y^2 with the condition that y(1)=4. I know that y= -1/(x^3 + c) but what do I do with the y(1)=4 part?
*Sunday, May 18, 2014 at 9:30pm*

**Calculus**

The marginal revenue for x items in dollars is given by R′(x)=−4.5x+6. Determine (a) the revenue function and (b) the demand function. I know the revenue function is R(x)=6x-2.25x^2 just by finding the antiderivative. demand = revenue - cost, but how do I even find...
*Sunday, May 18, 2014 at 9:08pm*

**Calculus**

Find f(x) if f′(x)=(−3)⋅x+(−1) and f(−4)=−1. I know if you find the antiderivative of f'(x) it is -3x^2/2 - x + c but what do I do next to find the function f(x)?
*Sunday, May 18, 2014 at 8:18pm*

**Calculus**

The rate at which an item depreciates is proportional to its value at that instant. If an item is presently values at $70,000 and 10 months later it is valued at $22,222, when in years will it be valued at $19,999? I'm not sure what formula to use...
*Sunday, May 18, 2014 at 7:20pm*

**Calculus**

An inverted conical tank is 3m tall and 1m in diameter at its widest point. The water is being pumped out of a spout 2m above the top of the tank. Recall that the density of water is = 1000kg/m^3 (a) Find the work needed to empty the tank if it is full. Include units. (b...
*Sunday, May 18, 2014 at 6:42pm*

**Calculus**

How long must 4500 dollars be left on deposit at 8 percent compounded quarterly to reach a total accumulation of 15825 dollars? I did A=P(1+ r/n)^nt so I got 15825 = 4500 ( 1 + 0.08/4)^4t, and got t = 3.24886 years...am I even using the right formula?
*Sunday, May 18, 2014 at 5:56pm*

**Calculus**

Solve for x log(base6)(x+3)−log(base6)(x−;5)=2. I tried to factor out the log(base6) and got (x+3)^x/(x-5)=2, but I don't know how to solve that...
*Sunday, May 18, 2014 at 5:14pm*

**Calculus**

Find A so that 5log(base5)16807 − 3log(base5)7 = log (base5)A I don't even know how to start this one...should I remove the 5 and 3 in front of the logs?
*Sunday, May 18, 2014 at 4:49pm*

**Calculus**

Using log2=.3010 and log5=.6990 compute log2000000. 100000/5 = 20000 so I just did 20000*.699 = 13980 and then added .301 which equals 13980.3 ^I know that was wrong
*Sunday, May 18, 2014 at 4:33pm*

**Calculus**

Use the Laws of logarithms to rewrite the expression log(1000000x^19)in a form with no logarithm of a product, quotient or power. After rewriting we have log(1000000x^19)= A + Blog(x)? I know B = 19, but what's A?
*Sunday, May 18, 2014 at 3:57pm*

**Calculus**

f(x)=[3x^13]e^(−7x) On which intervals is the function concave up and concave down? I know when you find the 2nd derivative, the x-values are 0, 1.34206, and 2.37222, and that the 2nd derivative > 0 at x=1.34205 and < 0 at 2.37222. How does this tell me the ...
*Sunday, May 18, 2014 at 4:16am*

**calculus**

Consider the motion of a particle of mass m falling vertically under the earth’s gravitational field, and suppose the downward motion is opposed by a frictional force p(v) dependent on the velocity v(t) of the particle. Then the velocity satisfies the equation mv0(t) = &#...
*Sunday, May 18, 2014 at 3:29am*

**Calculus**

A brand new stock is also called an initial public offering. In this model, the period immediately after the stock is issued offers excess returns on the stock—that is, the stock is selling for more than it is really worth. One such model predicts the percent ...
*Saturday, May 17, 2014 at 11:53pm*

**Calculus**

A brand new stock is also called an initial public offering. In this model, the period immediately after the stock is issued offers excess returns on the stock—that is, the stock is selling for more than it is really worth. One such model predicts the percent ...
*Saturday, May 17, 2014 at 5:51am*

**Calculus**

The quantity Q of radioactive carbon remaining in a 200-gram wood sample at time t is given by the expression Q(t)=200e^(−0.000225⋅t). How much radioactive carbon remains in the sample after 100500 years? I just plugged in 100500 as t and got 3.02375 grams as an ...
*Saturday, May 17, 2014 at 2:10am*

**Calculus**

determine f" if f(x)=sqrt(x^3+2)
*Friday, May 16, 2014 at 12:49am*

**Calculus**

If f(x1)>f(x2) for every x1>x2 then what is the behaviour of f(x)?
*Friday, May 16, 2014 at 12:44am*

**Calculus**

If f(x1)>f(x2) for every x1>x2, then what is the behaviour of f(x)? I believe that the answer is that f(x) is increasing but I do not know how to show my work for that
*Thursday, May 15, 2014 at 6:23pm*

**Calculus**

A movie theater wants to determine the price per ticket that should be charged in order to maximize its revenue. The theater can accommodate 2000 movie goers per night, but the average attendance is about 1400 people per night. The average ticket price is about $8.00. Market ...
*Thursday, May 15, 2014 at 6:20pm*

**Calculus**

How do you find the derivative of y=sinxtan^3(x)?
*Wednesday, May 14, 2014 at 10:48pm*

**Calculus**

How do you find the derivative of y=tan^2(x^4)?
*Wednesday, May 14, 2014 at 6:44pm*

**Calculus**

How do you find the derivative of f(x)=sin2x/cos2x
*Wednesday, May 14, 2014 at 2:06pm*

**Calculus**

How do you find the derivative of y=5sin(-x)
*Tuesday, May 13, 2014 at 7:53pm*

**Calculus**

Let R be the region enclosed by the graphs y=e^x, y=x^3, and the y axis. A.) find R B.) find the volume of the solid with base on region R and cross section perpendicular to the x axis. The cross sections are triangles with height equal to 3 times the length of their base.
*Tuesday, May 13, 2014 at 1:12pm*

**calculus please help!**

Find maxima and minima and points of inflection. f(x) = 2x^3 - 3x^2 -36x +100 on the interval [-6,4]
*Tuesday, May 13, 2014 at 11:13am*

**Calculus **

(i) A 20m chain with a mass-density of 3kg/m (coiled on the ground). How much work is performed lifting the chain so that it is fully extended (and one end touches the ground)? (ii) How much work is performed to lift 1/4 of the chain?
*Monday, May 12, 2014 at 11:01pm*

**Calculus **

(i) A 20m chain with a mass-density of 3kg/m (coiled on the ground). How much work is performed lifting the chain so that it is fully extended (and one end touches the ground)? (ii) How much work is performed to lift 1/4 of the chain?
*Monday, May 12, 2014 at 9:12pm*

**Calculus**

Farmer Jones has 480 feet of fence. She wishes to construct a rectangular pen divided into five separate pens, with one of the pens twice as large as each of the other four (see figure). She must use part of her 480 feet of fencing material to make the partitions. What should ...
*Monday, May 12, 2014 at 4:59pm*

**Calculus**

For the parabola y^2=4px, where p, the focal length, is a constant, the focal point, f(p,0), is on the x-axis. Point S is 10 units from the point F and the segment SF makes a 60degree angle with the x-axis. The slope of segment TF is twice the negative of the slope of the ...
*Sunday, May 11, 2014 at 11:30am*

**Calculus**

Given f'(x)=9/2x(3x^2+2)^1/2 (this is the derivative of y= sqrt[(3x^2+2)^3]) , state any values of x for which the function is not differentiable
*Saturday, May 10, 2014 at 7:15pm*

**calculus**

find the volume of solid inside the paraboloid z=9-x^2-y^2, outside the cylinder x^2+y^2=4 and above the xy-plane 1) solve using double integration of rectangular coordinate. 2) solve using double integration of polar coordinate 3)solve using triple intergation
*Saturday, May 10, 2014 at 7:05pm*

**calculus**

find the volume of solid inside the paraboloid z=9-x^2-y^2, outside the cylinder x^2+y^2=4 and above the xy-plane
*Saturday, May 10, 2014 at 6:44am*

**Math (Calculus)**

Determine the area of the region y=e^x,y=x^3
*Friday, May 9, 2014 at 11:50pm*

**Math (Calculus)**

Use the disc method to find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the indicated line. y=x^3, y=0, x=2 a)the x-axis b)the line x=4
*Friday, May 9, 2014 at 11:04pm*

**calculus-answer check**

Deermine the derivative of f(x)=[(3x^2+1)^3+1]^2. Express your answer in simplified form. For this I got 54x^6+162x^5+54x^4+108x^3+18x^2+18x+2
*Friday, May 9, 2014 at 10:41pm*

**Calculus Please Help **

Evaluate the indefinite integral Note: Use an upper-case "C" for the constant of integration. integral sqrt(100x^2-400)/x dx Ty
*Friday, May 9, 2014 at 10:19pm*

**Calculus **

If y=u^3+u^2-1, where u=1/(1-x), determine dy/dx at x=2
*Friday, May 9, 2014 at 9:21pm*

**Calculus **

1.a)Determine dy/dx if y= sqrt[(3x^2+2)^3] For this question, I got 9/2x(3x^2+2)^1/2 as my answer. b)State any values of x for which the function is not differentiable
*Friday, May 9, 2014 at 9:12pm*

**Calculus**

1. If y′= x(1+ y) and y > -1 , then y= A) y=sinx B) y=3x^2+C << C) y=Ce^1/2x^2-1 D) y=1/2e^x^2+C E) y=Csq(x+3) 2. If dy/dx = x cos x^2 and y = −3 when x = 0, when x = π, y = ___. A) -3.215 B) √2 << C) 1.647 D) 6 E) 3π 3. Suppose an ...
*Friday, May 9, 2014 at 7:23pm*

**Calculus**

Let s(t)=-5t^2+40t be the position equation for a rock thrown upwards. At what time t, in seconds, will the rock change directions?
*Friday, May 9, 2014 at 7:16pm*

**calculus-answer check**

1. Determine the slope of the tangent to the graph of y=4/x at (1,4) my answer is -4 2.What is the slope of the line perpendicular to y=(x-2)/(x+2) at (2,0) my answer is -4 3. For which value of x is the derivative of f(x)=(x-1)^10(x+2)^5 equal to 0? my answer is 1
*Friday, May 9, 2014 at 6:37pm*

**calculus-answer check**

Determine the slope of the tangent line to the curve y=(x^2+3x)(x^2-2) at x=-1. I got 3 as my answer although I am not too sure that it's correct. I found the derivative of the function and then substituted -1 into the equation.
*Friday, May 9, 2014 at 5:56pm*

**Calculus answer check**

Starting from rest, a man runs 10 metres along a straight path in t seconds. His position can be described by the function s(t)=0.7t^2. How long will it take him to reach the velocity of 4m/s? would the answer be 5.6 s? I started with s(t)=0.7t^2, then the velocity is 7/5t and...
*Friday, May 9, 2014 at 4:41pm*

**Calculus**

1) yy'-e^x= 0, and y=4 when x=0 means that: A)y=x-lnx^2+4 B)y^2=4x^2+3 C)y=-2x+1/2x^3 D)y^2=2e^x+14 E)1/2ln|x^2+4|+6 2) The rate of change of P with respect to t is directly proportional to (10-t) and inversely proportional to the cube root of P. The differential equation ...
*Friday, May 9, 2014 at 1:59pm*

**Calculus**

write the equation of line tangent to f(x)=(1/3x^3)-x^2+x-1 when x=1
*Friday, May 9, 2014 at 12:53am*

**Math (Calculus)**

Use the shell method to set up and evaluate the integral that gives the volume of the solid generated by revolving the plane region about the y-axis. y=4-x^2, y=0
*Thursday, May 8, 2014 at 10:55pm*

**Math (Calculus)**

Use the shell method to find the volume of the solid generated by revolving the plane region about the indicated line. y=4x-x^2, y=0, about the line x=5
*Thursday, May 8, 2014 at 10:53pm*

**Math (Calculus)**

Find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the y-axis. (Use Disc Method) y=3(2-x), y=0, x=0
*Thursday, May 8, 2014 at 10:52pm*

**Calculus **

Which of the following is a separable, first-order differential equation? A) dy/dx= x+y/2x B) dy/dx=x+y/x-y C) dy/dx=sinx << D) dy/dx=xy/x+y E) dy/dx= 2lnxy 2) The differential equation dy/dx=y/x^2 has a solution given by: A) y=C sqrt(x^2+4) B)y=C e^-1/x C)-1/2ex^2+C D) ...
*Thursday, May 8, 2014 at 9:20pm*

**calculus help**

Evaluate!!!! integral -10 to 10 ((2e^x)/(sinhx+coshx))dx Thanks!
*Thursday, May 8, 2014 at 12:32am*

**Calculus**

HELP....last question SOS HELP Consider the statement lim X-->1 X©ø-6X©÷+11X-6 / x-1 = 2 USING THE DEFINITIONS OF THE LIMIT STATE WHAT MUST BE TRUE FOR THE ABOVE LIMIT TO HOLD, THAT IS, FOR EVERY ¡¦, THERE IS ..., SO THAT¡¦...
*Wednesday, May 7, 2014 at 8:51pm*

**Calculus, Riemann **

IF ANYONE CAN PLEAAAASEEEE HELP ME Use the Riemann sum definition of the definite integral to show that b 3 ¡ò x©÷dx - b©ø -a©ø a Here, for simplicity, we assume b > a > 0. Be sure to clearly specify your mesh/grid xi, , ...
*Wednesday, May 7, 2014 at 8:27pm*

**calculus**

Find the interval of convergence of the series. ∑(sinx/10)^n
*Wednesday, May 7, 2014 at 7:34pm*

**Calculus**

How much should be deposited into an account today if it is to accumulate to $32400 in 30 years if the account bears interest at 8.01% compounded monthly? I did A = 32400(1 + 0.0801/12)^(12*30) = $355,375, but that's wrong...
*Wednesday, May 7, 2014 at 5:35pm*

**calculus help**

Find the derivative of the function. y = integral from cosx to sinx (ln(8+3v)) dv lower limit = cosx upper limit = sinx y'(x) = ????
*Wednesday, May 7, 2014 at 4:48pm*

**Calculus Help Please Urgent!!!**

Use the Midpoint Rule with the given value of n to approximate the integral. Round the answer to four decimal places. integral from o to pi/2 (2cos^3(x))dx , n = 4 M4 = ?????? Thanks!!!
*Wednesday, May 7, 2014 at 4:43pm*

**Calculus (lim)**

consider the statement lim x³-6x²+11x-6 / x-1 = 2 x->1 Using the definition of the limit, state what must be true for the above limit to hold, that is, for every ..., there is ..., so that.... Use a specific function and limit not just f and L. Verify the ...
*Wednesday, May 7, 2014 at 1:25pm*

**Calculus Riemann sum definition etc**

I am totally stumped... PLEASE if anyone can help we are going nuts...lol Use the Rieman sum definition of the definite integral to show that 3¡ò(there is a little "b" at top and little "a" at bottom 3¡ò x©÷dx = b©...
*Wednesday, May 7, 2014 at 1:06pm*

**Calculus**

SOS...help!!! please email me at 969e221 at g mail. com here is the question: Find the trapezoid of largest area that can be inscribed in the upper half of the ellipse x2/9 + y2/4 = 1 where the lower base of the trapezoid is on the x-axis and is 6 units long. I need to graph ...
*Wednesday, May 7, 2014 at 12:02pm*

**Math (Quadratic Equations)**

A field is bound on one side by a river. A farmer wants to enclose the other three sides of the field with fence in order to create a rectangular plot of land for his cows. If the farmer has 400m of fence to work with, determine the maximum possible area of the field and the ...
*Wednesday, May 7, 2014 at 11:40am*

**calculus**

Determine whether the given series converges or diverges, and find the sum if it converges. I dont understand, help!! Thnx! 1) 20+5+(5/4)+(5/16)+...
*Wednesday, May 7, 2014 at 1:13am*