# Is #f(x)=-sqrt(e^x -x^3-2x # concave or convex at #x=-1 #?

##### 1 Answer

May 15, 2017

#### Explanation:

Determine the concavity of a graph by finding the second derivative of the function, and the sign of

Differentiate using the chain rule:

Differentiate using the quotient rule:

Plug in

This value is negative because the numerator is negative while the denominator is positive.

Therefore,