Saturday

October 25, 2014

October 25, 2014

Posted by **Ellen** on Friday, July 20, 2012 at 9:23pm.

- math help -
**MathMate**, Friday, July 20, 2012 at 10:09pm1. Find f'(x)=-xe^((-x^2)/2)

2. plot f'(x) and find where f'(x) crosses the x-axis.

Note that e^((-x^2)/2)>0 ∀ x∈R. Therefore the sign is determined by the factor (-x), which is >0 for x∈(-∞0) and negative for x∈ (0,+∞).

3. Knowing that x is increasing when f'(x)>0 and decreasing when f'(x)<0, can you take it from here?

**Answer this Question**

**Related Questions**

Calculus - find the intervals where the function is increasing and the intervals...

Math - What is the domain? Use a graphing utility to determine the intervals in ...

Math(Help!!) - What is the domain? Use a graphing utility to determine the ...

Math(Please help) - What is the domain? Use a graphing utility to determine the...

Calculus - Consider the function f(x) = x - lnx. Find the intervals on which f(x...

Engineering Calculus - f(x)=((6x-3)/(x+6)) how do you find the intervals of ...

Math - determine the intervals over which the function is increasing, decreasing...

Business Calculus - Determine the intervals where f(x)=e^-x^2/2 is increasing ...

Need Help please - Determine the intervals where the function is increasing and ...

increasing and decreasing intervals - Have to find the intervals on which f(x...