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Calculus and Analysis

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

Determining the best place to sit at the movies based on a set of criteria.

A movie theater has a screen that is positioned 10 feet off the floor and is 25 feet high. The first row of seats is placed 9 feet from the screen and the rows are 3 feet apart. The floor of the seating area is inclined at an angle above the horizontal and the distance up the incline that you sit is x. The theater has 21 ro

Rate of change

1) The area of a circle is decreasing at the rate of 2 pie cm^2/s. At what rate is the radius of the circle decreasing when its area is 75 pie cm^2? 2)Find f'(-1), given f(y)=h(g(y)), h(2)=55, g(-1)=2, h'(2)=-1, and g'(-1)=7

Compound Interest Problems

If the tuition at a certain college is determined to cost $ 32000 in 10 years, how large must a trust fund that pays 7.5% compounded continuously be, in order for a child on her 8th birthday to ensure sufficient funds at age 18?

Differentiation/graphs

I have two problems (well, one problem with three parts and another one): 1. (a) Let f(x)=ax^2+bx+c, a does not equal zero, be a quadratic polynomial. How many points of inflection does the graph of f have? (b)Let f(x)=ax^3+bx^2+cx+d, a does not equal zero, be a cubic polynomial. How many points of inflection does the grap

Single-variable function

A robot is guided towards an object by a software algorithm that controls its position such that the path of the robot is approximately sinusoidal, with a period 2, as shown in Figure B4 (attached). (a) Show that the length l of any single-variable function f(x), between the limits of x=a and b, can be expressed by th

Mu''(t) + ku(t) = 0

Suppose m and k are positive numbers. Find u so that mu''(t) + ku(t)= 0 for all numbers t and u(0)=1 and u'(0)=2. (note: u'' = second derivative of u) Please clarify any shorthand that you are using. Thanks!

Ellipse, points where tangent line is vertical

Given the ellipse x2/4 + y2/9 = 1 What are the points where the tangent line is vertical? (In narrative, the problem reads: given the ellipse x squared divided by 4, plus y squared divided by 9, equals 1, what are the points where the tangent line is vertical? The problem is also attached in MS Word, in case you need it