Question

For what values of x is `f(x)=-2x^2-6x+4` concave or convex?

Answer 1

The function is concave everywhere.

Explanation:

Algebra

The graph is a parabola that opens downward. So it is concave.

Calculus

`f'(x) = -4x-6`

`f''(x) = -4`

Since `f''(x)` is negative for all `x`, the function is concave for all `x`.