Evaluate the indicated function for $f ( x ) = x ^ { 2 } - 5$ and $g ( x ) = x + 9$
$( f g ) ( - 1 )$
A) $- 32$
B) $- 48$
C) 46
D) 40
E) $- 50$

Question

Quizplus · Accepted Answer

The notation $(fg)(x)$ means the product of $f(x)$ and $g(x)$. First, find $f(-1)$ and $g(-1)$. For $f(-1) = (-1)^2 - 5 = 1 - 5 = -4$, and for $g(-1) = -1 + 9 = 8$. Then, $(fg)(-1) = f(-1) \cdot g(-1) = -4 \cdot 8 = -32$.

Evaluate the Indicated Function For f(x)=x2−5f ( x ) = x ^ { 2 } - 5f(x)=x2−5

Evaluate the Indicated Function For $f ( x ) = x ^ { 2 } - 5$