# How do you determine whether the function #g(x)=-x^2+3x+4# is concave up or concave down?

##### 1 Answer

Jul 27, 2015

#### Answer:

Two methods:

#### Explanation:

**Using calculus,** to determine concavity, investigate the sign of the second derivative.

Since

Which is to say:

**Using algebra,** the graph of this quadratic is a parabola. Since the coefficient of