Analyzing Functions

Question

For what values of x is the graph of  concave downward? 

Options:

1. x>4
2. x<-4
3. x>-4
4. No values of x

Answer 1

 

First, find some "anchor points" to see the shape of the curve:

for large +x, y is negative and approaching 0

for large - x, y is positive and approaching 0

at x = -4, the curve goes to infinity

Based on this, the curve is never concave (up or down)---CHECK this by plotting a graph.