Find the derivative of f(x)
f(x)=(x2+4)(3x-5)
f'(x)=9x2-10x+12
A guy is standing 10 feet from a tree. He wants to know how tall the tree is. The angle from his feet to the top of the tree is 60 degrees. How tall is the tree?
Don't compute
Height of the tree = 10tan(60)
y=ln(4x3)
find y'
y'=3/x
Find all critical numbers of the function f(x).
f(x)=x4+12x3+362+2
Critical numbers=-3,-6,0
find the limit of y=x2-64/x-8 when x approaches 8
lim when x approaches 8 = 16
Find f'(1)
f(x)=(2x2+4)(3x+5)/4x-9
f'(x)=48x3-122x2-180x-188/(4x-9)2
f'(1)=-442/25
Convert 7pi/6 to degrees
210 degrees
find f'(x)
f(x)=log2(sin(x))
f'(x)=cot(x)/ln(2)
For the following function, find the intervals where f(x) is increasing and decreasing.
f(x)=-5x-9
Decreasing on interval (-infinity,infinity)
Never increasing
Find where f(x) is discontinuous. Where f(x) is discontinuous, find the limit when x approaches the value where f(x) is discontinuous.
f(x)=x2-81/x-9
discontinuous @ x=9
lim when x approaches 9 = 18
find f'(0)
f(x)=(x2-3)(x2-sqrt(5))
f'(x)=(x2-3)(2x)+(x2-sqrt(5))(2x)
f'(0)=0
y=5sin(3x)
find y'
y'=15cos(3x)
find f'(x)
f(x)=2e3x^2
f'(x)=12xe3x^2
f(x)=(x+9)/(x+4)
The function is decreasing on the interval (-infinity,4), (-4,infinity)
A culture contains 25,000 bacteria, with the population increasing exponentially. The culture contains 40,000 bacteria after 12 hours. Find the value for k in the exponential equation giving the number of bacteria after t hours.
hint: y=yoekt
k=1/12ln(40000/25000)
find f'(x)
f(x)=-5(5x2+8)-6
f'(x)=300x(5x2+8)-7
find f'(x)
f(x)=cos(4x2)+3x4
f'(x)=-8xsin(4x2)+12x3
find y'
y=x3x
y=e3xln(x)
y'=3x3x(ln(x)+1)
Find the relative min and max of the function f(x).
f(x)=-x3-3x2+9x+5
min=(-3,-22)
max=(1,10)
For what values on the unit circle does cos(x)=0
x=pi/2 and 3pi/2
find y'
y=x2+2/(9x-7)6
y'=-36x2-14x-108/(9x-7)7
find y'
y=cos(sin(e2x))
y'=-2e2xsin(sin(e2x))cos(e2x)
find y'
y=7xlog7x
y'=(7x/xln7)+(log7x)(7xln7)
Find the open intervals where the function f(x) is concave up and down.
f(x)=7/(x-7)
Up: (-infinity,7)
Down: (7,infinity)
When and where is the exam tonight?
6:30-8pm W290 Chem Building