Sunday

April 19, 2015

April 19, 2015

**Calculus**

A bright light on the ground illuminates a wall 12 meters away. A man walks from the light straight toward the building at a speed of 2.3 m/s. The man is 2 meters tall. When the man is 4 meters from the building, how fast is the length of his shadow on the building decreasing?
*Sunday, October 19, 2014 at 8:27pm*

**Calculus**

A pulley system on a pier is used to pull boats towards the pier for docking. Suppose that a boat is being docked and has a rope attaching the boat's bow on one end and feeding through the pier's pulley system on the other end. The pulley system is 1 meter higher than ...
*Sunday, October 19, 2014 at 8:26pm*

**Calculus**

Find the value of a so that the tangent line to y = ln(x) at x = a is a line through the origin. I am unsure how to go about this.
*Sunday, October 19, 2014 at 7:18pm*

**Calculus**

find y' of 4(cos(x^3))^2 when x = 1. I got -24(1)(cos(1)(sin(1) = -0.4187 but the answer is -10.9.
*Sunday, October 19, 2014 at 5:59pm*

**Calculus**

Find an equation of the tangent line to the curve f(x) = (sins)^2 + 2tanx at x= pi/4. I worked through it and got y = 5x + 5/2 for my answer, but the answer key says that it is y - 5/2 = 5(x - pi/4). Why is the pi/4 in the answer? Thanks for any help!
*Sunday, October 19, 2014 at 3:53pm*

**calculus**

find the x-coordinate of all points on the curve y=12Xcos(5X)-(30*sqrt3*X^2) + 16, pi/5<X<2pi/5 where the tangent line passes through the point (0,16), (not on the curve) I have absolutely no idea how to solve this one
*Sunday, October 19, 2014 at 1:34pm*

**Calculus**

Find f''(1/2) using f(x) = ln(1-x). f'(x) = 1/(1-x) * -1 = -1/(1-x) so then using quotient rule: f''(x) = ((-1*-1) - ((1-x)(0))) / (1-x)^2 f''(1/2) = 1/(1-(1/2))^(2) = 4 Is this correct?
*Sunday, October 19, 2014 at 2:12am*

**Calculus**

What is the derivative of (ln(x))^x ? I have: f(x) = ln(x)^x f(x) = xlnx f'(x) = x/x + 1 * ln(x) f'(x) = 1 + ln(x) Is this correct?
*Sunday, October 19, 2014 at 1:50am*

**calculus**

can anyone help me with that question what is the domain of log(log(x)the base is 0.2)
*Saturday, October 18, 2014 at 10:57pm*

**calculus**

Use polar coordinates to find the volume of the given solid. Inside the sphere x^2+y^2+z^2=25 and outside the cylinder x^2+y^2=1
*Saturday, October 18, 2014 at 10:27pm*

**calculus**

Find the points of the paraboloid z=x^{2}+y^{2}-1 at which the normal line to the surface coincides with the line joining the origin to the point. What is the acute angle betwwen the normal and the z-axis at these points?
*Saturday, October 18, 2014 at 10:26pm*

**calculus**

A cable runs along the wall from C to P at a cost of $3 per meter, and straight from P to M at a cost of $5 per meter. If M is 16 meters from the nearest point A on the wall where P lies, and A is 50 mters from C, find the distance from C to P such that the cost of installing ...
*Saturday, October 18, 2014 at 10:25pm*

**calculus**

Find the points of the paraboloid z=x^{2}+y^{2}-1 at which the normal line to the surface coincides with the line joining the origin to the point. What is the acute angle betwwen the normal and the z-axis at these point
*Saturday, October 18, 2014 at 10:23pm*

**calculus**

use differentials to determine by approximately how many centimeters does the diagonal of a square table increase if its area is increased from 50 square centimeters to 54.45 square centimeters? Area= s^2 Diagonal= sqrt(2s^2) so, D= sqrt(2A) dD=A^(-1/2) dA dD= 50^(-1/2)* 4.45 ...
*Saturday, October 18, 2014 at 9:07pm*

**Calculus**

If G(x)=(x)/(1+2x), find G'(a) and use it to find an equation of the tangent line to the curve y=(x)/(1+2x) at the point (-1/4,-1/2). My answer: G'(a)=1/(1+2x)^2 Equation of tangent line: y= 4x+0.5
*Saturday, October 18, 2014 at 3:55pm*

**Calculus**

A pebble is dropped from an open window 100 meters above the ground. a) What is the velocity of the pebble after 2 seconds? b) What is the velocity of the pebble when it hits the ground?
*Saturday, October 18, 2014 at 3:07pm*

**Calculus**

Find the slope of the curve f(x)=1/(x^2+3). My answer: (-2x)/(x^2+3)^2
*Saturday, October 18, 2014 at 2:46pm*

**Calculus**

The number of bacteria after t hours in a controlled laboratory experiment is n=f(t). Suppose there is an unlimited amount of space and nutrients for the bacteria. Which do you think is larger, f'(5) or f'(10)? If the supply of nutrients is limited,would that affect ...
*Saturday, October 18, 2014 at 2:44pm*

**calculus**

2 given s(t)=3t +5t+3, find the instantaneous velocity when t i= 5.
*Saturday, October 18, 2014 at 12:17pm*

**calculus**

how would you represent the area outside given y= 4cos(2theta) but outside y=4 ?
*Saturday, October 18, 2014 at 11:11am*

**Calculus**

A rectangular field is to be enclosed by a fence and divided into three lots by fences parallel to one of the sides. Find the dimensions of the largest field that can be enclosed with 800 feet of fencing. Help me please!!!!!!!!!!! THANK YOU
*Saturday, October 18, 2014 at 11:05am*

**Calculus**

The cost of producing x ounces of gold from a new gold mine is C=f(x) dollars. Do you think the values of f'(x) will increase or decrease in the short term? What about the long term? Explain.
*Saturday, October 18, 2014 at 11:02am*

**DIFF CALCULUS**

A swimming pool is 12 meters long, 6 meters wide, 1 meter deep at the shallow end, and 3 meters deep at the deep end. Water is being pumped into the pool at ¼ cubic meter per minute, and there is 1 meter of water at the deep end. a. What percent of the pool is filled? ...
*Saturday, October 18, 2014 at 10:03am*

**calculus**

a ladder 6 feet long leans against a vertical building. the bottom of the ladder slides away from the building horizontally at rate of 1/2 ft/sec. A) at what rate is the top of the ladder sliding down the wall when the bottom of the ladder is 3 feet from the wall? b)at what ...
*Saturday, October 18, 2014 at 12:58am*

**Calculus**

The number of bacteria after t hours in a controlled laboratory experiment is n=f(t). Suppose there is an unlimited amount of space and nutrients for the bacteria. Which do you think is larger, f'(5) or f'(10)? If the supply of nutrients is limited,would that affect ...
*Friday, October 17, 2014 at 10:50pm*

**Calculus**

The cost of producing x ounces of gold from a new gold mine is C=f(x) dollars. Do you think the values of f'(x) will increase or decrease in the short term? What about the long term? Explain.
*Friday, October 17, 2014 at 10:44pm*

**calculus**

ind the point(s) on the cone z^2 = x^{2}+3y^{2} that are closest to the point (-1,-7,0)
*Friday, October 17, 2014 at 10:09pm*

**Calculus**

what is the limit of arcsinx as x approaches 1 from the left
*Friday, October 17, 2014 at 10:01pm*

**Calculus**

1. If the tangent line to y=f(x) at (4,3) passed through the point (0,2), find f(4) and f'(4). My answer: f(4)=3 f'(4)=1/4
*Friday, October 17, 2014 at 9:26pm*

**calculus**

A sample poll of 100 voters revealed the following information concerning three candidates A, B, and C who were running for three offices. 10 voted in favor of both A and B, 35 voted in favor of A or B but not C, 25 voted in favor of B but not A or C, 65 voted in favor of B or...
*Friday, October 17, 2014 at 8:59pm*

**Calculus**

Find the volume of the largest rectangular box with edges parallel to the axes that can be inscribed in the ellipsoid x^2/81+y^2/25+z^2/49=1
*Friday, October 17, 2014 at 8:39pm*

**calculus**

Use Lagrange multipliers to find the maximum and minimum values of f(x,y)=x^2y+3y^2-y subject to the constraintx^2+y^2less than or equal to 10
*Friday, October 17, 2014 at 8:36pm*

**calculus**

Given g(x) = (x + cosx)/(e^x - 2x^3 + 5). Find g'(x). Do not need to simplify.
*Friday, October 17, 2014 at 12:11pm*

**calculus**

Find the point on the surface z = 2x2+xy+3y2 where the tangent plane is parallel to the plane 8x-8y-z=5.
*Friday, October 17, 2014 at 12:09pm*

**CALCULUS**

Hi guys can you help me! Please teach me step by step.. I really need it. pls! Thank you......... A swimming pool is 12 meters long, 6 meters wide, 1 meter deep at the shallow end, and 3 meters deep at the deep end. Water is being pumped into the pool at ¼ cubic meter ...
*Friday, October 17, 2014 at 11:35am*

**Algebra/Pre-calculus (Quadratic Equations)**

A theatre company allows a group of 10 people to buy theatre tickets at a price of $28 per person. For each person in excess of 10, the price is decreased by $2 per person for everyone down to a minimum of $10 per person. What number of people will produce the maximum revenue ...
*Friday, October 17, 2014 at 10:35am*

**Calculus **

A tray of lasagna comes out of the oven at 200°F and is placed on a table where the surrounding room temperature is 70°F. The temperature T (in °F) of the lasagna is given by the function T(t)=e^94.86753-t)+70 , 0 ≤ t, where t is time (in hours) after taking ...
*Friday, October 17, 2014 at 10:34am*

**calculus**

6) The function f(x)=4x3−18x2−480x−2 is decreasing on the interval ? Enter your answer using the interval notation for open intervals. It is increasing on the interval(s) ? The function has a local maximum at ?
*Friday, October 17, 2014 at 10:27am*

**calculus**

A bright light on the ground illuminates a wall 12 meters away. A man walks from the light straight toward the building at a speed of 1.1 m/s. The man is 2 meters tall. When the man is 4 meters from the building, how fast is the length of his shadow on the building decreasing...
*Friday, October 17, 2014 at 10:21am*

**calculus**

2) Let g(s)= t(4−t)^1/2 on the interval [0,2]. Find the absolute maximum and absolute minimum of g(t) on this interval. Enter DNE if the absolute maximum or minimum does not exist. The absolute max occurs at t= . The absolute min occurs at t=
*Friday, October 17, 2014 at 10:21am*

**calculus**

f(x)=x2(x−24). So f is decreasing (and f′ is negative) on the interval (0,a) for a= ?
*Friday, October 17, 2014 at 10:20am*

**CALCULUS**

1. A rectangular package to be sent by a postal service can have a maximum combined length and girth (perimeter of a cross section) of 108 inches. Find the dimensions of the package of maximum volume that can be sent. (Assume the cross section is square.)
*Friday, October 17, 2014 at 10:05am*

**Calculus **

Suppose a ball is thrown straight up into the air, and the height of the ball above the ground is given by the function h(t) = 6 + 37t – 16t2, where h is in feet and t is in seconds. At what time t does the ball stop going up and start returning to earth?
*Friday, October 17, 2014 at 9:53am*

**diff calculus**

1.) triangular corner lot has perpendicular sides of lengths 120 feet and 160 feet. Find the dimensions of the largest rectangular building that can be constructed on the lot with sides parallel to the streets.
*Friday, October 17, 2014 at 7:26am*

**calculus**

f(x)= 3+4xe^{-5x}complete the sentences concerning the function a) the function f is decresing on the iterval...... b) the function f is increacing on the interval c) the function f is concave down on the interval d) the function f is concave up on the interva
*Friday, October 17, 2014 at 1:07am*

**calculus**

can you find a sequence{an} such that {an} diverges, and the series of an converges? justify
*Friday, October 17, 2014 at 1:06am*

**calculus**

If f(x) = 3 cos^2(x) − 6 sin(x) 0 ≤ x ≤ 2π Find the intervals of increase and decrease, the intervals of concave up and concave down, local maximum values, local minimum values, and inflection point
*Friday, October 17, 2014 at 1:04am*

**Calculus **

The population of a colony of bacteria is modeled by the function p(x)=50(e^-x - e^-x^2)+10 ,for 0 ≤ x, where population P is in thousands, x is in hours, and x = 0 corresponds to the moment of introduction of a certain chemical into the colony's environment. At ...
*Thursday, October 16, 2014 at 11:54pm*

**Calculus **

The population of a colony of bacteria is modeled by the function p(x)=50(e^-x - e^-x^2)+10 , for 0 ≤ x, where population P is in thousands, x is in hours, and x = 0 corresponds to the moment of introduction of a certain chemical into the colony's environment. At ...
*Thursday, October 16, 2014 at 11:52pm*

**Calculus..**

Two particles are moving in straight lines. The displacement (meters) of particle 1 is given by the function s(t)= cos(4x), where t is in seconds. The displacement (meters) of particle 2 is given by the function s(t)= t^3/3-t^2/2 +2(t) , where t is in seconds. Find the first ...
*Thursday, October 16, 2014 at 11:28pm*

**AP Calculus**

In the answer space below, provide the larger of the two positive integers that add up to 60 and have the largest possible product.
*Thursday, October 16, 2014 at 10:37pm*

**AP Calculus**

If 600 cm2 of material is available to make a box with a square base and a closed top, find the maximum volume of the box in cubic centimeters. Answer to the nearest cubic centimeter without commas. For example, if the answer is 2,000 write 2000.
*Thursday, October 16, 2014 at 10:36pm*

**calculus**

Find the point on the plane z = 6x + 9y + 1 closest to the point P = (1, 0, 0). Hint: Minimize the square of the distance. (x, y, z) =
*Thursday, October 16, 2014 at 9:41pm*

**calculus**

find the coordinates of the centroid bounded by y=25x^2 and y=4. the region is covered by a thin flat plate
*Thursday, October 16, 2014 at 9:36pm*

**Calculus**

Derivative of the implicit Function: arctan(x^5y)=xy^5 Here is where I am at. I am pretty frustrated: arctan(x^5y)-xy^5=0 1/1+(x^5y)^2 * (d/dx(x^5)*y+x^5*d/dx(y))-(d/dx(x)*y^5+x*d/dx(y^5))=0 1/(1+x^5y)^2 * (5x^4y+x^5dy/dx) - (y^5+x^5y^4dy/dx) (5x^4y)/[(1+x^5y)^2] + (x^...
*Thursday, October 16, 2014 at 2:52pm*

**Calculus**

A 13 foot ladder is leaning against the house when it's base starts to slide away. By the time is 12 feet from the house the base is moving at the rate of 5 ft/sec. 1.How fast is the top of the ladder sliding down the wall at that moment? 2. At what rate is the angle theta...
*Thursday, October 16, 2014 at 8:26am*

**calculus**

Find the maximum and minimum values of f(x, y) = xy on the ellipse 8\!x^{2} + y^{2} = 9.
*Thursday, October 16, 2014 at 12:36am*

**calculus**

Find the center of mass in the 1st quadrant of the circle x^2+y^2=4 where rho(x,y)=k(x^2+y^2) Thanks.
*Wednesday, October 15, 2014 at 8:14pm*

**REALLY HARD CALCULUS PROBLEMMMM PLEASE HELP ME???**

A circular swimming pool has a diameter of 16 m, the sides are 3 m high, and the depth of the water is 2.5 m. How much work (in Joules) is required to pump all of the water over the side? (The acceleration due to gravity is 9.8 m/s 2 and the density of water is 1000 kg/m 3 .) ...
*Wednesday, October 15, 2014 at 4:31pm*

**Integral Calculus**

A force of 4 pounds is required to hold a spring stretched 0.1 feet beyond its natural length. How much work (in foot-pounds) is done in stretching the spring from its natural length to 0.6 feet beyond its natural length?
*Wednesday, October 15, 2014 at 4:28pm*

**calculus**

Use iterated integral to find the area enclosed by r=2sin2(theta). How do i graph this?
*Wednesday, October 15, 2014 at 12:15pm*

**Calculus problem (PLEASE HELP!!)**

The diameter of a human pupil in millimetres is given by D= (2 + 4x^-0.3) / (1 + x^-0.3) where x is the luminance measured in candelas per square metre. Using this function,what is the diameter of the pupil when there is no light? What happens to the diameter of the pupil as ...
*Wednesday, October 15, 2014 at 9:02am*

**Calculus (Need help)**

Not sure how do do this. Please help? Find all values of a and b so that the function is continuous for all x E R. f(x)= −3a + 4(x^5)b x ≤ −1 { ax − 2b −1 < x < 1 3x^2 − bx + a x ≥ 1
*Wednesday, October 15, 2014 at 7:21am*

**Calculus I**

lim x→ ∞ of e^(−x) sin√x A little lost. Help would be appreciated.
*Wednesday, October 15, 2014 at 5:49am*

**pre-calculus**

You are given a pair of equations, one representing a supply curve and the other representing a demand curve, where p is the unit price for x items. -45 x^2 - 74.5199999999995 x + 15921.36 - 1224.72 p = 0 and 54 x^2 + 1743.12 x + 13880.16 - 6940.08 p = 0 a. Identify which is ...
*Tuesday, October 14, 2014 at 10:01pm*

**pre-calculus**

It has been found that the supply of lamps varies linearly with its price. When the price per item was $ 94.67 ,64 items are supplied; When the price was $ 134.67 , 124 items are supplied. How many lamps are supplied when the price per item is $ 118.00 ? What is the lowest ...
*Tuesday, October 14, 2014 at 9:58pm*

**Calculus**

Find all values of a and b so that the following function is continuous for all x ∈ R. f(x) = −3a + 4x^5(b) x ≤ −1 ax − 2b −1 < x < 1 3x^2 − bx + a x ≥ 1
*Tuesday, October 14, 2014 at 6:32pm*

**calculus**

The half-life of Radium-223 is 11.43 days. If a sample has a mass of 400 mg, find the mass (in mg) that remains after 6 days
*Tuesday, October 14, 2014 at 4:04pm*

**Foundations and Pre-Calculus Math 10**

Find the radius of a cone with a height of 3m and a volume of 30m cubed. So far I have 90m cubed / 3m = pi(r^)3m/3m. Then I get stuck. Help! I'm really bad at math. ):
*Tuesday, October 14, 2014 at 1:30pm*

**pre-calculus**

The Hotel Florence has 550 rooms. Currently the hotel is filled . The daily rental is $ 700 per room. For every $ 14 increase in rent the demand for rooms decreases by 7 rooms. Let x = the number of $ 14 increases that can be made. What should x be so as to maximize the ...
*Monday, October 13, 2014 at 10:51pm*

**calculus**

Use diferenciales para estimar la cantidad de estaño en una lata cerrada de este metal con diámetro de 8 cm y altura de 12 cm, si el estaño tiene 0.004 cm de grosor.
*Monday, October 13, 2014 at 7:12pm*

**Pre-calculus**

You are given a pair of equations, one representing a supply curve and the other representing a demand curve, where p is the unit price for x items. 80 p + x - 380 = 0 and 84 p - x - 40 = 0 Identify which is the supply curve and demand curve and the appropriate domain. Put the...
*Monday, October 13, 2014 at 6:23pm*

**calculus**

Find the dimensions of the rectangular box having the largest volume and surface area 60 square units
*Sunday, October 12, 2014 at 6:49pm*

**Calculus**

Gravel is being dumped from a conveyor belt at a rate of 25 ft3/min, and its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal. How fast is the height of the pile increasing when the pile is 6 ft high? (Round your ...
*Sunday, October 12, 2014 at 6:25pm*

**calculus**

The volume of a cube is increased from 729 cubic centimetres to 849.285 cubic centimetres. Use differentials to determine: a) by approximately how many centimetres the side length of the cube increases ? B) by approximately how many square centimetres does the surface area of ...
*Sunday, October 12, 2014 at 3:18pm*

**Calculus**

A water trough is 9 m long and has a cross-section in the shape of an isosceles trapezoid that is 40 cm wide at the bottom, 80 cm wide at the top, and has height 40 cm. If the trough is being filled with water at the rate of 0.3 m3/min how fast is the water level rising when ...
*Sunday, October 12, 2014 at 2:21pm*

**calculus**

use differentials to determine by approximately how many square centimeters does the area of a square table increase if its diagonal is increased from 4 centimeters to 4.092 centimeters the question is The area of table increases by approximately (??) square centimetres
*Saturday, October 11, 2014 at 5:52pm*

**statistics**

On this semesters final exam, john scored 72 on his calculus exam and 53 on his statistics exam. The z score for both exams was the same. Which on would he do better on? a. calculus b.statistics c. the exam scores are equivalent
*Saturday, October 11, 2014 at 5:52pm*

**Calculus**

The volume of a cube is increased from 729 cubic centimetres to 849.285 cubic centimetres Use differentials to determine : (a) by approximately how many centimetres does the side length of the cube increase? (b)by approximately how many centimetres does the surface area of the...
*Saturday, October 11, 2014 at 3:50pm*

**calculus**

the surface area of a cube is increased from 24 square centimeters to 26.016 square centimeters . use differentials to determine: (1) by approximately how many centimeters does the side length of the cube increase? (2) by approximately how many cubic centimeters does the ...
*Saturday, October 11, 2014 at 2:55pm*

**statistics**

On this semesters final exam, john scored 72 on his calculus exam and 53 on his statistics exam. The z score for both exams was the same. Which on would he do better on? a. calculus b.statistics c. the exam scores are equivalent
*Friday, October 10, 2014 at 8:17pm*

**calculus**

Verify the given linear approximation at a = 0. Then determine the values of x for which the linear approximation is accurate to within 0.1. (Enter your answer using interval notation. Round your answer to two decimal places.) tan x ≈ x
*Friday, October 10, 2014 at 6:20pm*

**pre-calculus**

You are given a pair of equations, one representing a supply curve and the other representing a demand curve, where p is the unit price for x items. 80 p + x - 380 = 0 and 84 p - x - 40 = 0 a. Identify which is the supply curve and demand curve and the appropriate domain. Put ...
*Friday, October 10, 2014 at 5:06pm*

**economics **

First,label the following scenarios as to whether they would create a producer or consumer surplus. Then, after you have labeled each scenario, calculate the ensuing surplus. Claire is trying to sell her used calculus textbook online. She asks for $150 or best offer and is ...
*Friday, October 10, 2014 at 11:09am*

**calculus**

f(x,y)=2xe^y-3ye^-x derive second order
*Friday, October 10, 2014 at 1:07am*

**Calculus **

Would you please check my answer to make sure I did it right? Bus travel, a bus company finds that monthly costs for one particular year were given by C(t) = 100 + t^2 dollars after t months. After t months the company had P(t) =1000 +t^2 passengers per month. How fast is its...
*Thursday, October 9, 2014 at 5:19pm*

**pre calculus**

sinB + cosB cotB = cscB
*Thursday, October 9, 2014 at 9:28am*

**Calculus**

Some cowboys plan to build a rectangular corral in a canyon. They have 500 feet of fencing to use for three sides of the rectangle (the canyon wall is used for the 4th side). a) What is the maximum area that they can fence in? b) What are the dimensions of the rectangle?
*Wednesday, October 8, 2014 at 8:33pm*

**statistics**

Correction On this semesters final exam, john scored 72 on his calculus exam, (class distribution (u=65, \?=3.57)\) ) and 53 on his statistics exam (class distribution :u=49, ?=2.04. Which exam should he get the better grade. z1=72-65/3.57=1.960 Z2=53-49/2.04=1.960
*Wednesday, October 8, 2014 at 8:11pm*

**statistics**

On this semesters final exam, john scored 72 on his calculus exam, (class distribution (u=65, \?=3.57)\) ) and 53 on his statistics exam (class distribution :u=49, ?=2.04. Which exam should he get the better grade. z1=72-65/3.57=1.960 Z2=53-49/3.57=1.120
*Wednesday, October 8, 2014 at 8:03pm*

**Calculus I**

cos(2x)−cos(x) = -((sin^2)x + 1/4) Need help solving.
*Wednesday, October 8, 2014 at 11:38am*

**CALCULUS HELP NEEDED ASAP!**

Having a lot of trouble with this one: Q) 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 remaining in the lungs even after the deepest exhalation (ie the minimum ...
*Wednesday, October 8, 2014 at 11:36am*

**pre-calculus**

A machine worth $10,000 new and having a scrap value of $1000 is to be depreciated linearly over an 18-year life. What will be the value of the machine after 9 years?
*Tuesday, October 7, 2014 at 11:03pm*

**calculus**

An airplane flys at a constant altitude of 2 miles and a constant speed of 600 miles per hour on a straight course that will take it directly over a kangaroo on the ground. How fast is the angle of elevation of the kangaroo's line of sight increasing when the distance from...
*Tuesday, October 7, 2014 at 10:09pm*

**Statistics**

On this semesters final exam, john scored 72 on his calculus exam, (class distribution (u=65, \σ=3.57)\) ) and 53 on his statistics exam (class distribution :u=49, σ=2.04. Which exam should he get the better grade. z1=72-65/3.57=1.960 Z2=53-49/3.57=1.120
*Tuesday, October 7, 2014 at 9:48pm*

**Calculus Please Help!**

Not sure how to do this. Asked before but it was hard to type out the symbols in the equation, so I have a screenshot below. exactly Please help! s.yimg(.)com/hd/answers/i/36cad89caaff4061bf38ed04166cbd76_A.png?a=answers&mr=0&x=1412733166&s=...
*Tuesday, October 7, 2014 at 7:54pm*

**Calculus question**

It looks very complicated and I do not know how to even start. Any help would be immensely appreciated. A pendulum has a mass, m, suspended from a rod of length L. At the time t = 0, the pendulum is pulled through an angle θ0 > 0 to the right and given an initial ...
*Tuesday, October 7, 2014 at 6:55pm*

**Calculus**

An airplane flys at a constant altitude of 2 miles and a constant speed of 600 miles per hour on a straight course that will take it directly over a kangaroo on the ground. How fast is the angle of elevation of the kangaroo's line of sight increasing when the distance from...
*Tuesday, October 7, 2014 at 6:46pm*

**Calculus help please**

I have to evaluate the following: tan((sin^-1)(2/7)) and sin^-1 (sin(17pi/6)) Please help.
*Tuesday, October 7, 2014 at 6:44pm*

**Calculus**

slope of tan line to the ellipse is -4x/y for x^(2)/4+y^(2)/16 Are there any points where the slope is not defined? (Enter them as comma-separated ordered-pairs, e.g., (1,3), (-2,5). Enter none if there are no such points.) slope is undefined at
*Tuesday, October 7, 2014 at 5:05pm*