Extrema
Derivatives of Inverse Functions
Implicit Functions
Related Rates & Optimization
Bits & Bobs
100

Determine the intervals of concavity and classify the critical points of f(x) = 4x^3 -3x^2 - 36x + 5

Concavity: (-inf,1/4) up, (1/4,inf) down

Min @ x=2

Max @ x = -3/2

100

Find (f-1)`(8) for f(x) = x^3

1/12

100

Find d2y/dx2 for sqrt(x)*sqrt(y)=2

2y/x


100

A farmer needs to construct two adjoining rectangular pens of identical areas. If each pen is to have an area of 1200 square feet, what dimensions. will minimize the cost of fencing

x = 40 ft

y = 30 ft

100

Determine if the MVT applies to this function, if so find the c for which it is valid.

h(x) = 1/2 * X^3 -x^2 on [-2,2]

c = -2/3

200

Find the extrema of f(x) = (3x^2 +1)/(x-2) using the first derivative test

Max: x = (12- sqrt(156))/6

min: x =(12 + sqrt(156))/6

200

Find (f-1)`(pi/2) for f(x)=2tan^-1(x)

1

200

Find the points with vertical and horizontal tangent lines for (x^2 -2x + 5)*y = 5

Horizontal: (1,4/5)

Vertical: (3, 5/6), (-2, 5/13)


200

The shape of a Norman window can be approximated by a rectangle with a semicircle on top. What dimensions will admit the maximum amount of light if the perimeter of the window is fixed as P

w = 2P/(4 + pi)

h = P/(4+pi)

200

The position of a particle at time t is represented by s(t) = 1/3 * t^3 -3t^2 + 8t - 5. When is the particle at rest? 

t = 4, t=2

300

Classify extrema using the first derivative test for f(x) = sin^2(x) + 1

Maxima: pi/2 + npi

Minima: npi

300

Find (f-1)`(b) for g(x) = (3x^8 + x^3 + 1)^(3/2) given b=g(1)

2/(8sqrt(5))

300

Find the coordinates when dy/dx = 2/3 for 3x^2 + 6 = 3xy

(sqrt(6), 4sqrt(6)/3)

(-sqrt(6), -4sqrt(6)/3)

300

A fisherman is reeling in a fish at a rate of 20 centimeters per second. If the tip of his fishing rod is 4.5 meters above water and we assume the fish lies along the top of the water the entire time, how fast is the fish approaching when 7.5 meters of fishing line are still out?

Approach at -.125 meters per second

300

Apply L'Hôpital's rule for 2x/(x2 -3x+4)

infinity = limit

400

Use the first and second derivative test to find increasing or decreasing intervals and points of inflection

Intervals: decreasing (-inf,-sqrt(3)/2), (sqrt(3)/2,inf)

increasing (-sqrt(3)/2,sqrt(3)/2)

inflection points: x = 0 

400

Find (f-1)`(b) for g(x) = x^17 + 2x^11 -2x+3 for b = 4

1/37

400

Find a classify extrema for 3x^2 + 2y^2 = 16 by implicit differentiation

Max: (0, 2rt(2))

Min: (0, -2rt(2))

400

The position of a ball at time t is s(t) = t3-6t2+9t. Find when the acceleration when the velocity is equal to 0

a(1) = -6

a(3) = 6

500

What is the derivative of arccsc

-1/(|x|sqrt(x2-1))