Question

For what values of x is `f(x)= -x^2+3x+4` concave or convex?

Answer 1

`-x^2+3x+4` is concave for all `x`

Explanation:

A polynomial of the second grade has the same concavity everywhere, as its second derivative is constant.

In this case:

`f''(x) = -2`

So `f(x)` is concave for all `x`.