f(x)=(2)/(x^2-9)

Use interval notation to indicate where is increasing and decreasing

Question

f(x)=(2)/(x^2-9)

Use interval notation to indicate where is increasing and decreasing

anonymous · Answer

Do you know how to take the derivative of a function?

anonymous · Answer

-(4x)/((x-3)^2(x+3)^2)

anonymous · Answer

Okay, now do you know how to find the second derivative?

anonymous · Answer

To find the inflection point, you find the second derivative, and set it equal to 0. Then solve.

anonymous · Answer

Yeah,

(12(x^2+3))/((x^2-9)^3)

anonymous · Answer

There are no inflection points, I'm trying to find where f(x) is increasing and decreasing in interval notation.

anonymous · Answer

Give me a min to solve this.

anonymous · Answer

So, only 1 point which is 0. so the function is increasing from -infinity to 0 and decreasing from 0 to infinity.

anonymous · Answer

Instead of infinity.

anonymous · Answer

Sorry, increases from -3 to 0. and decreases from 0 to 3.

anonymous · Answer

Nope, that's not right.

anonymous · Answer

-3<=x<=0, and 0<=x<=3.

anonymous · Answer

It's like this -infinity<=x<-3 union -3<x<=0. Same goes for decreasing.

anonymous · Answer

I can't seem to write the decreasing one correctly...
(INF,0)U(0,3)?

anonymous · Answer

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