Question

y = 3 - l t-3 l

y' = 9 - t^2

The solutions says that only 3 is a critical number. Why not -3 also?

Answer 1

of which equation? -3 should also be a critical number of the second equation, but I don't understand how the first equation relates to the problem

Answer 2

well ultimately i have to find the extrema of the y = 3 - l t-3 l ....so i guess i figured that absolute values had something to do with it but i wasn't exactly sure

Answer 3

wait a second.. how did u differentiate it?

Answer 4

i did what you told me...square the inside and take the square root

Answer 5

but i dont think this will work..

Answer 6

thats how i got y'

Answer 7

uhmm in that case it would work but im not sure about here...

Answer 8

wait it does work..

Answer 9

i honestly have no idea why, ask ur teacher lol

Answer 10

wait, what was the original question?