Question

find where function is increasing or decreasing and find local min and local max using 1st derivative test and use a sign diagram

Answer 1

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Answer 2

if it goes from increasing to decreasing at a critical number then you have at that critical number a max and you can find the max value by evaluating the original function at that x.

if it goes from decreasing to increasing at a critical number then you have at that critical number a min and you can find the min value by evaluating the original function at that x.

Answer 3

so we definitely need to find the derivative of your given function there first

Answer 4

then find where your derivative function=0

Answer 5

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Answer 6

and find where the derivative function doesn't exist

Answer 7

oh number b?

Answer 8

you used quotient rule?

Answer 9

okay well i just want to know after you find the critical points for teh sign diagram do you use teh derivative function and plug values in to see if it is positive or not in the sign diagram or do you use the original equation

Answer 10

the original function tells you where the critical number occurs
the derivative function just tells you if the tangent line has slope pos or neg or zero or doesn't exist

Answer 11

so the original function will tell you the max and min value

Answer 12

okay thanks