Thursday

February 11, 2016
**Calculus **

a rectangular lot adjacent to a highway is to be enclosed by a fencing cost $ 2.50 per foot.along the highway $1.50 per foot on the other sides find the dimension of the largest lot that can be fenced off for $270. Thank you God bless. Badly need it
*Thursday, February 11, 2016 by Zhel*

**calculus**

25pi/3=1/2xsquare root of 100x^2 and plus 50 arcsin(x/10)
*Thursday, February 11, 2016 by sara*

**Math**

If a valid time on a 12 hour time period has the hour hand and minute hand switched, how many times will that result in another valid time? I have found 11, which is when the hour hand points at the same place as the minute hand. I know there is much more, but I can't ...
*Wednesday, February 10, 2016 by Andre post for Steve*

**Calculus with Analytical Geometry 1**

You take out a 15 year mortgage for $20,000 at the rate of interest 4% compounded monthly. If, after 5 years, interest rate drop and you wish to refinance. How much remains to be on your mortgage?
*Tuesday, February 9, 2016 by Sherianna*

**calculus**

The table below gives selected values for the function f(x). Use a trapezoidal estimation, with 6 trapezoids to approximate the value of . x 1 1.1 1.2 1.5 1.7 1.9 2.0 f(x) 1 3 4 6 7 8 10
*Tuesday, February 9, 2016 by Jason*

**Calculus**

If a valid time on a 12 hour time period has the hour hand and minute hand switched, how many times will that result in another valid time? I have found 11, which is when the hour hand points at the same place as the minute hand. I know there is much more, but I can't ...
*Tuesday, February 9, 2016 by Andre post for Steve*

**Calculus 2**

Sketch the region in the first quadrant enclosed by y=7/x, y=2x, and y=x/2. Decide whether to integrate with respect to x or y. Then find the area of the region.
*Tuesday, February 9, 2016 by Henry*

**Calculus**

Consider the following depiction of a tank with radius r = 9 meters with a spout of height h = 4.5 meters. A tank is is half full of oil that has a density of 900 kg/m3. Find the work W required to pump the oil out of the spout. (Use 9.8 m/s2 for g and 3.14 for π. Round ...
*Monday, February 8, 2016 by Kaitlyn*

**calculus 1**

the average temperature in Hartford can be expressed as t = f(m) where m is month (January = 1, etc.) and t is the average daily high temperature for the month in degrees F. 1) what is the meaning of f'(m)? rate of change of the average temperature (in degrees F) as the ...
*Monday, February 8, 2016 by sal*

**Calculus**

When selling lemonade for 50 cents per cup, Diana can sell 40 cups per day. She observes that the number of cups sold per day decreases by 2 for every 5-cent increase in the price of a cup of lemonade. Determine a formula for the number cups C of lemonade sold each day as a ...
*Monday, February 8, 2016 by Barbara T.*

**pre-calculus**

x|x-3|<2 I did x(x-3)<2 or x(x-3)<2 and simplified it to x^2-3x<2 and am not sure how to simplify it further and express it in interval notation. Help!
*Monday, February 8, 2016 by Emily*

**Calculus (double integral) PLEASE HELP!**

Evaluate double integral ln((x-y)/(x+y)) dy dx where the double integral region is the triangle with vertices (1,0),(4,3), (4,1). Hint: use a transformation with the Jacobian.
*Monday, February 8, 2016 by David*

**Calculus (Jacobian question)**

Evaluate double integral ln((x-y)/(x+y)) dy dx where the double integral region is the triangle with vertices (1,0),(4,3), (4,1). Hint: use a transformation with the Jacobian.
*Sunday, February 7, 2016 by David*

**calculus**

Integrate : (x^3)dx/sqrt. of (3x^2 - 5) Let x=sqrt(5/3)secant theta dx=sqrt(5/3)secant theta tangent theta Sqrt. (3x^2-5) = sqrt. (5/3) tangent theta
*Sunday, February 7, 2016 by mathemagician*

**Calculus**

Find the volume bounded above by parabolic z = 6 - x^2 - y^2 and below by z= 2x^2 + y^2
*Sunday, February 7, 2016 by Lucie*

**calculus**

The maker of an automobile advertises that it takes 10 seconds to accelerate from 30 kilometers per hour to 90 kilometers per hour. Assuming constant acceleration, compute the following. (a) The acceleration in meters per second per second (Round your answer to three decimal ...
*Sunday, February 7, 2016 by harvey*

**calculus**

The maker of an automobile advertises that it takes 10 seconds to accelerate from 30 kilometers per hour to 90 kilometers per hour. Assuming constant acceleration, compute the following distance traveled in 10 seconds
*Sunday, February 7, 2016 by ged*

**Calculus**

How do I use three vertices to calculate the area of a triangle? The three vertices are (0,0), (2,1), and (-1,6). I've figured out that the equations of the lines that make up the triangle are y = -6x, y = (1/2)x, and y = (-5/3)x + 4.34ish. Now I have to integrate to find ...
*Saturday, February 6, 2016 by Anonymous*

** Calculus (polar coordinates)**

Use polar coordinates to set up the double integral x dA, where the bounds are given by the region lying in the intersection of the 2 circles r = 2 sin (theta) and r = 2 cos theta. Thanks for any help!
*Saturday, February 6, 2016 by Lucie*

**calculus**

How to calculate the volume of rotating object formed by the area between curve y=x^2 and y=3x which is rotating through : a. x axis b. y axis ; using skin tube methode
*Saturday, February 6, 2016 by bruge*

**Pre-Calculus**

x = 2/7 is a root of 49x^3 - 126x^2 + 60x - 8 = 0. Factor the polynomial completely and list all real solutions. My answer: (x - 2)(7x - 2)^2 = 0 factored, and the solutions are x = 2 and x = 2/7.
*Saturday, February 6, 2016 by Anonymous*

**Pre-Calculus**

f(x) = 7x^3 + 8x^2 - 3x + 8 Find f(7) using synthetic division, and list the numbers in the bottom row of the division. My answer: The numbers in the bottom row are 7, 58, 403, and 2829. The answer is 7x^2 + 58x + 403 + 2829/x - 7.
*Saturday, February 6, 2016 by Anonymous*

**Calculus**

The fuel consumption (gallons per hour) of a car traveling at a speed of v miles per hour is c = f(v). 1) What is the meaning of the derivative f ' (v)? answer: rate of change of fuel consumption as miles go up 2) What are its units? answer: miles per gallon 3) Write a ...
*Saturday, February 6, 2016 by Maia *

**Calculus with Analytical Geometry **

Find the present value (PV) of the annuity with each payment of $3500 at the end of each year for 3 years in an account that pays 6% compounded annually.
*Saturday, February 6, 2016 by Sherianna*

**Calculus**

An architect wants to design a window in the shape of a rectangle capped by a semicircle. If the perimeter of the window is constrained to be 24 feet, what dimensions should the architect choose for the window in order to admit the greatest amount of light?
*Saturday, February 6, 2016 by Ethan*

**Calculus**

What is the derivative of f^3(g(x)) where both are continuous functions? I used chain rule and got 3f^2(g(x))f'(g(x))g'(x) but it is not right.
*Friday, February 5, 2016 by Andre*

**Calculus**

y = f(x) = x^2 - 3 x (a) Find the average rate of change of y with respect to x in the following intervals. from x = 2 to x = 3 Incorrect: Your answer is incorrect. from x = 2 to x = 2.5 Incorrect: Your answer is incorrect. from x = 2 to x = 2.1 Incorrect: Your answer is ...
*Friday, February 5, 2016 by Anonymous*

**Calculus**

Using the definition of the derivative, find the equation of the tangent line to y=2x-1/2 at (1/2,-1) Thanks!!
*Friday, February 5, 2016 by Sarah*

**Calculus**

one top of a tower 50 m high is clock 3m in diameter. where a man 5 feet 6 inches stand on the ground so that he could have a possible view of the clock.
*Friday, February 5, 2016 by Anonymous*

**calculus**

A flea moves along the line y = -3 according to the equation: x = t^3 - 9t^2 + 24t where x is its x coordinate at time t secs. Determine: 1) the position, velocity, and acceleration of the flea at time 3 secs. Answer: position - 3^3 - 9(3)^2 + 24(3) = 18 units/second velocity...
*Thursday, February 4, 2016 by molly*

**Calculus**

Two hallways, one 8 feet wide and the other 6 feet wide, meet at right angles. Determine the length of the longest ladder that can be carried horizontally from one hallway into the other.
*Thursday, February 4, 2016 by Anonymous*

**Calculus**

Two hallways, one 8 feet wide and the other 6 feet wide, meet at right angles. Determine the length of the longest ladder that can be carried horizontally from one hallway into the other. Thank you so much..
*Thursday, February 4, 2016 by Anonymous*

**Calculus**

Two hallways, one 8 feet wide and the other 6 feet wide, meet at right angles. Determine the length of the longest ladder that can be carried horizontally from one hallway into the other.
*Thursday, February 4, 2016 by Anonymous*

**Calculus**

A stone is thrown straight up 6 feet from the ground (it is released 18 feet above the ground). When it is released it is travelling at the rate of 100 feet per second. a) Find the velocity function. b) Find the position function. c) How high does the stone go? d) How long ...
*Thursday, February 4, 2016 by Lois*

**Calculus PLEASE HELP! PLEASE PLEASE PLEASE**

A long, straight wire of length 2L on the y-axis carries a current I. According to the Biot-Savart Law, the magnitude of the magnetic field due to the current at a point (a,0) is given by B(a)= (mu sub 0 multiply by I) divided by 4pi times the integral from -L to L of (Sine ...
*Thursday, February 4, 2016 by Sathira*

**Calculus**

A 10-foot section of gutter is made from a 12-inch-wide strip of sheet metal by folding up 4-inch strips on each side so that they make the same angle with the bottom of the gutter. Determine the depth of the gutter that has the greatest carrying capacity.
*Thursday, February 4, 2016 by Anonymous*

**Calculus**

A 10-foot section of gutter is made from a 12-inch-wide strip of sheet metal by folding up 4-inch strips on each side so that they make the same angle with the bottom of the gutter. Determine the depth of the gutter that has the greatest carrying capacity.
*Thursday, February 4, 2016 by Anonymous*

**Calculus**

Consider the following depiction of a tank with radius r = 9 meters with a spout of height h = 4.5 meters. A tank is half full of oil that has a density of 900 kg/m3. Find the work W required to pump the oil out of the spout. (Use 9.8 m/s2 for g and 3.14 for π. Round your...
*Wednesday, February 3, 2016 by Kaitlyn*

**Calculus**

During the initial stage of launching a spacecraft vertically, the acceleration a(in m/s^2) is a=6t^2. Find the velocity in the spacecraft after 6 seconds.
*Wednesday, February 3, 2016 by Anonymous*

**Calculus**

s(t) = t^2 - 6t + 5 models the motion of a person cycling along Rte 66 where s(t) is the number of miles north of Los Angeles the person is at time t hours. 1) Write functions for the cyclist's velocity and acceleration at any time t. 2) Find the position and velocity of ...
*Wednesday, February 3, 2016 by Tulu*

**calculus 1**

lim x---> 2 4x+1/3x-4 illustrate definition 2 by finding values of delta that correspond to epsilon=0.5 and epsilon= 0.1 I having trouble setting this up. do i set up two different functions then divide? 0.2898 thats the answer i got....
*Wednesday, February 3, 2016 by feather*

**Calculus**

s(t) = t^2 - 6t + 5 models the motion of a person cycling along Rte 66 where s(t) is the number of miles north of Los Angeles the person is at time t hours. 1) Write functions for the cyclist's velocity and acceleration at any time t. 2) Find the position and velocity of ...
*Wednesday, February 3, 2016 by Tulu*

**Calculus**

Find the area bounded by the indicated curves. y=x^2, y=0, x=2
*Wednesday, February 3, 2016 by Anonymous*

**Math (calculus ) **

A company buys an office machine for $5200 on January 1 of a given year. the machine is expected to last for eight years at the end of which time its trade in value or salvage value will be 1100$. if the company figures the decline in value to be the same each year than the ...
*Tuesday, February 2, 2016 by Jenna*

**Calculus(PLZ HELP)**

A serving bowl has an inside diameter of 12 inches and a depth of 4 inches. The bowl is fashioned from part of a sphere. Find the capacity (volume) of the bowl.
*Tuesday, February 2, 2016 by Jack*

**Calculus**

1. Prove that (f(x+h)-f(x-h))/2=f'(x) 2. Prove that any parabola sastifies the equation (f(x+h)-f(x-h))/2=f'(x) For the first question, I tried to solve it but there is an extra h tacked on to one side. I have no clue what to do for the second question.
*Monday, February 1, 2016 by Andre*

**Calculus**

If f(x)=x^4, compute f(-2) and f'(-2) f(-2)=___ <--- ?
*Sunday, January 31, 2016 by Dominick*

**calculus**

a closed rectangular box whose base is twice as long as it is wide has a volume of 36000 cm^3.the material for the top cost 10 centavo per sq cm,that for the sides and bottom cost 5 centavos per sq cm.find the dimensions that will make the cost of making the box a minimum
*Sunday, January 31, 2016 by emil*

**Calculus and Vectors**

Afarmer requires two rectangular corrals with a combined area of 200m^2. The cost of the fencing facing the road is $25/m while the sides cost $20/m. The back side of the corrals will be against the side of the barn, which is 40m long. what is the minimum cost?
*Sunday, January 31, 2016 by Matthew Slaney*

**Calculus and Vectors**

The volume of a large soup can is 1L. The cost of the top is $0.002/cm^2 while the sides and bottom cost $0.001/cm^2.Find the minimum cost to pruduce the can given that the radius must be between 5cm and 10cm for shipping purposes.
*Sunday, January 31, 2016 by Matthew Slaney*

**Calculus and Vectors**

A farmer has 54 m of fencing with which to build two rectangular animal pens with a common side. If the area of the pens if to be maximized, what are their dimensions?
*Sunday, January 31, 2016 by Matthew Slaney*

**Calculus and Vectors**

you want to make a box out of a piece of tin 20cm by 20cm by cutting the squares out of the corners and folding them up the sides. If the box is to have a maximum volume, what are their dimensions?
*Sunday, January 31, 2016 by Matthew Slaney*

**Calculus Plz Help**

If f(x)=x^4, compute f(-2) and f'(-2) f(-2)=___ <--- ?
*Sunday, January 31, 2016 by Dominick*

**Calculus**

Does anyone know how to solve, ln((3x-2)/(x-1))<0
*Sunday, January 31, 2016 by Em*

**calculus**

The demand for your hand-made skateboards, in weekly sales, is q = −4p + 600 if the selling price is $p. You are prepared to supply q = 6p − 400 per week at the price $p. What price should you sell your skateboards for so that there is neither a shortage nor a ...
*Saturday, January 30, 2016 by jay*

**Calculus**

Find for dy/dx 4 – xy = y^3.
*Friday, January 29, 2016 by Mel*

**Calculus**

Could someone help with this limit problem? lim x-->1 of ((sqrt(6-x))-2)/((sqrt(10-x)-3)) I tried to rationalize the denominator and numerator but it didn't work!
*Friday, January 29, 2016 by Em*

**Pre-calculus**

Hooke's Law states that the distance a spring will stretch beyond its natural length varies directly with the force applied to the spring. A force of 12 pounds is needed to stretch a certain spring 9 inches beyond its natural length. Find a formula that models the length a...
*Thursday, January 28, 2016 by Sami*

**Calculus**

Find the slope of the curve y=x^4 at x=4 The slope of the curve at x=4 is ___.
*Thursday, January 28, 2016 by Dominick*

**Calculus**

Could someone help with this limit problem? lim x-->1 of ((sqrt(6-x))-2)/((sqrt(10-x)-3)) I tried to rationalize the denominator and numerator but it didn't work!
*Thursday, January 28, 2016 by Em*

**Calculus**

Just wondering if anyone can help with this ln question! -Solve the following ln(x+1)+ln(x-1)=2 thanks!!
*Thursday, January 28, 2016 by Sophie*

**Calculus**

I don't know how to go about this question. The number of elephants in a park is estimated to be p(t)=7500/(1+749e^-0.15t) Where t is the time in years and t=0 corresponds to the year 1930. Find the inverse p(t) and the interpretation of that.
*Thursday, January 28, 2016 by Lilly*

**Calculus**

I don't know how to go about this question. The number of elephants in a park is estimated to be p(t)=7500/(1+749e^-0.15t) Where t is the time in years and t=0 corresponds to the year 1930. Find the inverse p(t) and the interpretation of that.
*Thursday, January 28, 2016 by Lilly*

**calculus**

Drug concentration is defined by; c(t)= 0.2t÷t^2+1 mg/cm^3...when is the concentration increasing/ decreasing (between 0 and 4hours)?
*Wednesday, January 27, 2016 by cayla*

**calculus 2**

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line. y = x, y = 0, x = 2, x = 6; about x = 1
*Wednesday, January 27, 2016 by TayB*

**calculus 2**

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line. y = 3 sin x, y = 3 cos x, 0 ≤ x ≤ π/4; about y = −1
*Wednesday, January 27, 2016 by TayB*

**calculus 2**

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line. y = 3x^4, y = 3x, x ≥ 0; about the x-axis
*Wednesday, January 27, 2016 by TayB*

**Calculus**

Find the implicit differentiation for each. 1) x^2 = (x-y) / (x+y) 2) (x+y)^3 + (x-y)^3 = x^4 + y^4
*Tuesday, January 26, 2016 by Maia*

**Calculus**

A cylindrical jar of radius 5 cm contains water to a depth of 8 cm. the water from jar is poured at a constant rate into a hemispherical bowl. After t seconds, the depth of the water in the bowl is x cm and the volume, V of water is given as 1/3πh^2(18-h). Given that all ...
*Tuesday, January 26, 2016 by RK*

**Calculus**

Implicit Differentiation: Find dy/dx for each. Leave answers in terms of both x and y. 1) 1/y + 1/x = 1 + y^2 2) -(x^2 / y^2)
*Monday, January 25, 2016 by Yani*

**Pre-Calculus**

The question is "Find parametric equations for the line with the given properties: Slope -2, passing through (-10, -20)." I don't even know where to begin, or what to do. Please help! This is an example problem, not the main homework problem, I just need to know ...
*Monday, January 25, 2016 by James *

**calculus 2**

Find the area of the region bounded by the parabola y = 5x^2, the tangent line to this parabola at (3, 45), and the x-axis.
*Monday, January 25, 2016 by TayB*

**calculus 2**

Sketch the region enclosed by the given curves. Find its area. y=7cos pi x, y=12x^2-3
*Monday, January 25, 2016 by TayB*

**Pre-Calculus**

Two cities are due north of each other. One city has a latitude of 32¢ª45'12" and the second city has a latitude of 51¢ª12'45". Assuming that the earth is a sphere with a radius of 4000 miles, how far apart are the two cities?
*Sunday, January 24, 2016 by Rhodora*

**Calculus**

Please help me find the limit: lim x--> 2 ((1/3)-1/sqrt(x))/)x-9)
*Sunday, January 24, 2016 by Sally*

**Calculus**

What is the first derivative of the following function: f(x) = a^(-bx)? (I am lost with this question)
*Sunday, January 24, 2016 by Leo*

**Pre-Algebra Calculus**

NEED HELP PLEASE Mixture Problems 1.Joe created a metal containing 40% platinum by combining two other metals. One of these other metals weighed 12 lb. and contained 45% platinum. If the other weighed 3 lb. then what percent of it was platinum? 2. 12 gal. of a saline solution ...
*Saturday, January 23, 2016 by michele*

**Calculus**

Suppose that 5 J of work is needed to stretch a spring from its natural length of 28 cm to a length of 36 cm. (a) How much work is needed to stretch the spring from 32 cm to 34 cm? (Round your answer to two decimal places.) (b) How far beyond its natural length will a force of...
*Saturday, January 23, 2016 by Kaitlyn*

**calculus 2**

Use a graph to find approximate x-coordinates of the points of intersection of the given curves. Then find (approximately) the area of the region bounded by the curves. (Round your answer to two decimal places.) y = 8x^2− 3x, y = x^3−8x+ 2
*Friday, January 22, 2016 by TayB*

**calculus 2**

The birth rate of a population is b(t) = 2000e^0.022t people per year and the death rate is d(t)= 1460e^0.017t people per year, find the area between these curves for 0 ≤ t ≤ 10. (Round your answer to the nearest integer.)
*Friday, January 22, 2016 by TayB*

**calculus 2**

Find the area of the region bounded by the parabola y = 3x^2, the tangent line to this parabola at (1, 3), and the x-axis.
*Friday, January 22, 2016 by TayB*

**Calculus**

Which of the following integrals correctly computes the volume formed when the region bounded by the curves x^2 + y^2 = 100, x = 6, and y = 0 is rotated around the y-axis? I've narrowed it down to either pi∫(sqrt(100-y^2)-6)^2 dy or pi∫(sqrt(100-y^2)^2-6^2) dy ...
*Friday, January 22, 2016 by John*

**Calculus**

Find the volume of the solid formed by revolving the region bounded by the graphs of y = x^2, x = 4, and y = 1 about the y-axis. I'm supposed to use this equation right? piR^2-x^r^2. and then change y=x^2 to x=sqrty. Thats all I got.
*Friday, January 22, 2016 by John*

**Calculus**

Find the number a such that the line x = a divides the region bounded by the curves x = y^2 − 1 and the y-axis into 2 regions with equal area. Give your answer correct to 3 decimal places.
*Friday, January 22, 2016 by John*

**pre calculus**

The diameter of the wheels on your car (including the tires) is 25 inches. You are going to drive 218 miles today. Each of your wheels is going to turn by an angle of how many degrees? Hint: A mile has 5280 feet, a foot has 12 inches, and the circumference of a circle with a ...
*Thursday, January 21, 2016 by Dunni*

**pre calculus**

You are building a (rectangular) pool in your backyard. It measures 30m in the north-south direction and 25 meters east-west. (Some pool!) The bottom of the pool is a slanted plane so that it's 1m deep along the southern edge and 10m deep along the northern edge. (As I ...
*Thursday, January 21, 2016 by Dunni*

**Calculus**

Hello, could somebody please help me out with the following question? I would greatly appreciate some assistance. Find all values of x in the interval [0, 2π] that satisfy the equation 3|tanx(x)|=3
*Thursday, January 21, 2016 by Constantine*

**Calculus**

Let f(t)=(1)/(t) Find a value of t such that the average rate of change of f(t) from 1 to t equals 14. t= ____
*Thursday, January 21, 2016 by Kendra*

**Calculus**

Find all values of x in the interval [0, 2π] that satisfy the equation. (Enter your answers as a comma-separated list.) 18 + 9 cos(2x) = 27 cos(x)
*Wednesday, January 20, 2016 by Riwo*

**Pre-calculus**

A rectangular package to be sent by a delivery service can have a maximum combined length (y) and girth (perimeter of its cross section) of 300 inches. Assume that the width and height are the same (x). Find the equation for the volume of the box in terms of x alone as an ...
*Wednesday, January 20, 2016 by Anonymous*

**Pre-calculus**

A rectangular package to be sent by a delivery service can have a maximum combined length (y) and girth (perimeter of its cross section) of 300 inches. Assume that the width and height are the same (x). Find the equation for the volume of the box in terms of x alone as an ...
*Wednesday, January 20, 2016 by Anonymous*

**Differential Calculus**

Determine all local extrema, concavity and inflection point/s for y = -2cos(x) in (0, 2Pi). Test by both First Derivative Test and Second Derivative Test and sketch the graph.
*Wednesday, January 20, 2016 by Sel*

**Calculus**

Find the minimum distance between the curves y=e^x and y=lnx. Hint: Use the fact that e^x and lnx are inverse relationships. I have no idea where to start. Thanks! calculus - Reiny, Monday, January 18, 2016 at 9:02pm to get you going: let P(a , e^a) and Q(b, lnb) be the ...
*Tuesday, January 19, 2016 by Samuel for Reiny*

**Math CALCULUS HELP PLEASE**

Tidal volume is the volume of air displaced in the lungs between inhalation and exhalation (the amount of air in a breath). The residual volume is given by the amount remaining in the lungs even after the deepest exhalation (i.e. the minimum amount of air remaining in the ...
*Tuesday, January 19, 2016 by Brad*

**Calculus**

The table below shows some values of a linear function f and an exponential function g. Fill in exact values for each of the missing entries. X 0 1 2 3 4 f(x) 25 375 g(x) 25 375
*Tuesday, January 19, 2016 by Leanna*

**Calculus**

Suppose that f(t)=Qoa^1=Qo(1+r)^t with f(4)=72.2 and f(10)=176.7. Find what a is and what r is.
*Tuesday, January 19, 2016 by Leanna*

**Calculus**

Use the identity sin^2x+cos^2x=1 and the fact that sin^2x and cos^2x are mirror images in [0,pi/2], evaluate the integral from (0-pi/2) of sin^2xdx. I know how to calculate the integral using another trig identity, but I'm confused about how to solve this one.
*Tuesday, January 19, 2016 by Rostrastics*

**Calculus**

Evaluate using substitution ∫(2x^5+6x)^3(5x^4+3)dx where b=0 and a=-1 I got to here and then got stuck u=5x^4+3 du=x^5+3x+C ∫(2x^5+6x)^3 u 1/(x^5+3x+C) ∫(x^5+3x)^3 u
*Tuesday, January 19, 2016 by John*

**Calculus**

Find the interval on which the curve of ∫ 6/(1+2t+t^2) where b=0 and a=x is concave up. Heres my work but im not sure at all g '(x) = 6/(1+2x+x^2) g ''(x) = -(2+2x)/[(1+2x+x^2)^2] upward when g ''(x) > 0. - (2+2x) > 0 x < -1
*Tuesday, January 19, 2016 by John*

**Calculus**

Graph the curve. Find the exact length of the curve. x = 2et cos(t), y = 2et sin(t), 0 ≤ t ≤ π
*Tuesday, January 19, 2016 by Kaitlyn*