CPM Homework Help : PC3 Problem 10-90

Use a calculator to graph the function $f(x) = \frac { 12 x } { x ^ { 2 } + 4 }$ , determine where the function is:

Calculator OK

Hint:

Trace the curve from left to right with your finger. When your finger moves 'uphill' the function is increasing.

More Help:

The curve is concave up where it looks like a cup that is right-side up.