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Calculus and Analysis

A minimization fencing problem.

A rectangular field is going to be enclosed and divided into two separate rectangular areas. (Areas do not have to be equal). Find the minimum fencing that is required if the total area of the field is 1200m2.

Working with infinite sequences and series.

If series Sum(an) and Sum(bn) with positive terms are convergent, is the series Sum(an*bn) converegent? Note: 1. Sum replaces the symbol for summation 2. an and bn are nth elements of the two series

Calculating rates of change in a loan situation.

The formula for the loan one can get with a payment of $P paying monthly for 15 years at an interest rate of r is: L=(12P/r)[1-(1+(r/12))^(-180)] a.) Find dL/dt, the rate of change of the loan with respect to time. (Here, t is the time that is passing, not the t in the original function if you know the loan. Trea

Exponential growth and decay

A leaking oil tank has a capacity of 500 000 liters of oil. The rate of leakage depends on the pressure of oil remaining in the tank and the pressure depends on the height of oil. When the tank is half-full, it loses 20L/min. How long goes it take to lose 15 000L from half-full?

Explaination for derivatives

Explaination for derivatives related to exponential and logarithmic functions ,formulae used to solve them and solutions to some problems. All problems are in the solution file

What is the equation of three bisecting solid rods centered at the origin?

Hello, What is the equation of three bisecting solid rods centered at the origin? Given 3 solid rods of length 3 and diameter 1. One rod is on the x-axis One rod is on the y-axis and One rod is on the z-axis Each is centered at the origin and is perpendicular to the other rods in each axis. Need equation in rectan

When to use the Chain Rule

The key is whether or not you are plugging the result of a function into another function. The idea is shown by contrasting the procedures for taking the derivatives of sin(x^2) and x^2*sin(x).

Euclidean space

Compute the distance from a point b = (1, 0, 0, 1)^T to a line which passes through two points (0, 1, 1, 0)^T and (0, 1, 0, 2)^T. Here ^T denotes the operation of transposition, i.e. the points are represented by column-vectors instead of row-vectors.

Calculating rates of separation for related rates.

Northbound ship A leaves the harbour at 10:00 with a speed of 12km/h. Westbound ship B leaves the same harbour at 10:30 with a speed of 16km/h. (a) How fast are the ships separating at 11:30? (b) When is their rate of separation 18.86 km/h

Chain rule/derivatives HW

What did I do wrong? 1. Find f'(x) when f(x)= 5x(sinx + cosx) My answer: cos(4x^2)- sin(6x^2)/(5x^2) 2. Find f'(x) when f(x)= ((x^3) + 4x + 4))^2 My answer: 6x^2(x^3 + 4x + 4) 3. Find f'(x) when f(x)= (3x + 8)^-3 My answer: -6(3x + 8) 4. Find f'(x) when f(x)= Sq root of (5x + 8) My answer: x/5x + 8 5. Find f'(x) when f(

Finding the surface area of the intersection of two cylinders.

Find the surface area of the solid that is the intersection of the two solid cylinders: x^2 + z^2 <= k^2 (x squared plus z squared is less than or equal to a constant squared) AND x^2 + y^2 <= k^2 (x squared plus y squared is less than or equal to the same constant squared) What is my f(x,y)? What are my limits of integr

Having difficulty with algebra in calculus

Find intervals on which the function is: (a) increasing (b) decreasing (c) concave up (d) concave down find any (e) local extreme values and (f) inflection points for the equation y = x to the 4/5 power times(2-x)

Dissecting a trig function

Let f be the function defined by f(x)=sin squared x - sinx for 0<or=x<or=(3pi)over 2. a. find the x- intercepts of the graph of f b.find the intervals on which f is increasing c. find the absolute maximum and absolute minimum value of f. Justify your answer.

Tan line and velocity problems

The parabola y = (x^2) + 3 has two tangents which pass through the point (0, -2). One is tangent to the to the parabola at (A, A^2 + 3) and the other at (-A, A^2 + 3). Find (the positive number) ? If a ball is thrown vertically upward from the roof of 64ft foot building with a velocity of 96 ft/sec, its height after t seconds

Implicit differentiation

Find dy/dx by implicit differentiation of the following: x^4-y^4-x+y=10 x^3y^3-x^2y^2+y=19 Any help would be appreciated! Thank you

Rate of change

Ichiro hits the ball and runs toward first base with a speed of 25 feet per second. The shortstop, who is exactly 40 feet in from third base on the baseline, gets the ball exactly 1.7 seconds after Ichiro started running (assume he runs at a constant rate.) At what rate is Ichiro's distance to the shortstop increasing at the m

Finding the rate of change.

A series of swells passes through a group of surfers. They notice that for a few minutes, the waves pass through at regular intervals: every 14 seconds. Let t=0 be the time when the wave is at its lowest point. The maximum instantaneous increase in height of the wave is 2.25 feet per second. a. Find r(t), the rate of chang

Limit points

Prove that the point p is a limit point of the point set X if and only if each open point set containing p contains a point in X which is different from p. Prove without using sequences. Only use the def. of open set, open interval, and that the point p is a limit point of the point set X means that each open interval containing