Question

Determine the derivative, all the critical numbers and the intervals of increase and decrease
y=-5x²+20x+2

Answer 1

\[\huge y'=-10x+20\]
\[\huge 0=-10x+20\]
\[x=2\]

Answer 2

i get :
intervals of increase x<2
intervals of decrease x>2

but the answer key says the opposite

Answer 3

when
\[y \prime >0, \]
then increasing.

Answer 4

what's in intervals of increase / decrease tho?

Answer 5

I got the same answer as you @burhan101
intervals of increase x<2
intervals of decrease x>2

Answer 6

x>2 it decreases
x<2 it increases.

Answer 7

Right...I as well @koymoi ...I think maybe your answer key is wrong @burhan101

Answer 8

think the answer key's wrong then ?

Answer 9

yes

Answer 10

yeah, i thought it was a fairly straight forward question

Answer 11

graph it and ull know for sure