The function `f(x)=(9-x^(2))^(2)` increases in

Options

A. `(-3,0)uu(3,oo)`
B. `(-oo,-3)uu(3,oo)`
C. `(-oo,-3)uu(0,3)`
D. `(-3,3)`

Answer

A

Explanation

Given `f(x)=(9-x^(2))^(2)`
`impliesf'(x)=2(9-x^(2))(-2x)`
Now put `f'(x)=0`
`implies2(9-x^(2))(-2x)=0`
`impliesx=0,+-3`

`:'f'(x)` is increasing in `(-3,0)uu(3,oo)`