Limits
Derivatives
Integrals
Rates
Miscellaneous
100

limx→2 (x3+4x2-3)

21

100

y=x20

dy/dx=20x19

100

∫(x3+x2-x)dx

(x4/4)+(x3/3)-(x2/2)+C

100

A circular pool of water is expanding at the rate of 16π in2/sec. At what rate is the radius expanding when the radius is 4in?

A=πr2

dA/dt=2πr dr/dt

16π=2π(4)dr/dt

dr/dt=2in/sec

100

sin2θ+cos2θ=

1+tan2θ=

1+cot2θ=

1

sec2θ

csc2θ

200

lim x→1 (x4+x2-1)/(x2+5)

1/6

200

y=7x1/2

dy/dx=(7/2)x-1/2

200

∫(dx/(9+x2))

1/3 tan-1(x/3)+C

200

A 25 foot long ladder is leaning against a wall and sliding toward the floor. If the foot of the ladder is sliding away from the base of the wall at a rate of 15ft/sec, how fast is the top of the ladder sliding down the wall when the top of the ladder is 7 feet from the ground? 

x2+y2=252

2x dx/dt+2y dy/dt=0

dx/dt=15, y=7, x=24

2(24)(15)+2(7)(dy/dt)=0

dy/dt=-360/7 ft/sec


200

sin(π/2 -θ)=

cos(π/2 -θ)=

tan(π/2 -θ)=

cosθ

sinθ

cotθ

300

lim x→0 (tan x)/(x)

1

300

y=3x4+8x10

dy/dx=12x3+80x9

300

∫sec23xdx

(tan3x)/3 +C

300

A spherical balloon is expanding at a rate of 60π in3/sec. How fast is the surface area of the balloon expanding when the radius of the balloon is 4in?

V=4/3πr3

A=4πr2

dV/dt=4πr2dr/dt

60π=4π(4)2dr/dt

dr/dt=15/16in/sec

dA/dt=8πrdr/dt

dA/dt=8π(4)(15/16)=30π in2/sec

300

steps to solving differential equations

1. separate variables

2. integrate

3. +C

3. solve for c, x, or y

4. use to approximate/ find tangent line

400

lim x→infinity (5x7-3x)/(16x6-3x)




0
400

y=50x5+(3/x)-7x-5/3

dy/dx=250x4-(3/x2)+((35/3)x-8/3)

400

∫10x(5x2-3)6dx

((5x2-3)7)/7 +C

400

An underground conical tank, standing on its vertex, is being filled with water at the rate of 18π ft3/min. If the tank has a height of 30 feet and a radius of 15 feet, how fast is the water level rising when the water is 12 feet deep?

r=h/2

V=1/3π(h/2)

h=πh3/12

dV/dt=(π/12)3hdh/dt

18π=(π/12)3(12)2dh/dt

dh/dt=1/2 ft/min

400

y'=

y"=

y'=0

y"=0

slope

concavity

a possible max/min

a possible point of inflection

500

lim x→infinity (xe-2x)

0

500

find d2y/dxof y=√5x3+x

dy/dx=1/2(5x3+x)-1/2(15x2+1)

d2y/dx2=1/2(5x3+x)-1/2(30x)+(15x2+1)[-1/4(5x3+x)-3/2(15x2+1)]

500

∫sinxdx [0, π/4] + ∫cosxdx [-π/4, 0]

1

500

A circle is increasing in area at the rate of 16π in2/sec. How fast is the radius increasing when the radius is 2 in?

dA/dt=2πrdr/dt

16π=2π(2)dr/dt

dr/dt=4 in/sec

500

Determine the area of the region bounded by        y=(1/(x+2)), y=(x+2)2, x=−(3/2), x=1

(67/8)−ln(1/2)−ln(3)

=7.9695