Given f (x) = x² + 8x and g (x) = x4, choose

the expression for (fºg) (x).

Answer: fg (x) = 16x² + 32x

Method:

First you must substitute g (x) into f (x).

Where the x is in the equation f (x) substitute the equation of g (x).

So it should be fg (x) = (x4) ² + 8 (x4).

Then simplify the equation to

fg (x) = 16x² + 32x