Question

The function f is given by F(x)=X^4+X^2-2. On which intervals is f increasing? i know im supposed to set f'x=0 but im not getting any of same answer choices.

Answer 1

f'(x)=4x^3+2x=0

Answer 2

Solve and factor ...

Answer 3

i factored first and made it 2x(x^2+1)=0

Answer 4

am i right?

Answer 5

solutions are x=0 and ...

Answer 6

and?

Answer 7

can we solve (x^2+1)=0 or is there only one solution?

Answer 8

isnt that x=1?

Answer 9

Let's check

1^2 + 1 = 0??

Answer 10

oh right .lol

Answer 11

Find the first derivative. If it is positive, the function is increasing.

Answer 12

So we have 0 as a solution ....

How do we find increasing or decreasing?

Answer 13

dont u plug in values above and less?

Answer 14

factored wrong