Posted by Andrea on .
At what interval is e^(5x^2) concave up?
I know the second derivative is
100x^2*e^5x^210*e^5x^2
but I just can not figure this one out.
Thank you for your help!

Calculus 
Damon,
first
http://www.wolframalpha.com/input/?i=plot++e^%285x^2%29 
Calculus 
Damon,
first
http://www.wolframalpha.com/input/?i=plot++e^%285x^2%29
Then this for second derivative and graph
https://www.wolframalpha.com/input/?i=second+derivative+of+e^%285x^2%29 
Calculus 
Damon,
Note that you did the second derivative correctly. It is easier to write it their way y" = 10e^(5x^2)(10x^21)
It is zero at x = +/ .316 
Calculus 
Damon,
so it is positive for x>.316
and for x <.316