## anonymous 5 years ago f(x)=(x^2+10)(1-x^2) find interval of increasing, decreasing, concave up, concave down, local max and min and infection point

1. anonymous

Did you take the derivative?

2. anonymous

Yes

3. anonymous

What did you end up with?

4. anonymous

2(1-x^2)-2(x^2+10)

5. anonymous

That's not quite right by the product rule $\frac{d}{dx}[(x^2+10)(1-x^2)]$ $=(x^2+10)\frac{d}{dx} [(1-x^2)] + (1-x^2) \frac{d}{dx} [(x^2+10)]$ $=-2x(x^2+10) + 2x(1-x^2) = 2x(1-x^2 -x^2 -10)$ $=2x(-2x^2 -9) = -2x(2x^2 + 9)$