Compute $f ^ { \prime } ( a )$ for $a = 0$ .
$f ( x ) = - x ^ { 2 } - 8 x$
A)8
B) $- 10$
C) 0
D) $- 8$
E) 10

Name: Compute $f ^ { \prime } ( a )$ for $a = 0$ . $f ( x ) = - x ^ { 2 } - 8 x$ A)8 B) $- 10$ C) 0 D) $- 8$ E) 10
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Question

Compute $f ^ { \prime } ( a )$ for $a = 0$ .  
  $f ( x ) = - x ^ { 2 } - 8 x$  
A)8
B)   $- 10$
C)  0
D)   $- 8$
E)  10

Quizplus · Accepted Answer

The derivative of $f(x) = -x^2 - 8x$ is $f'(x) = -2x - 8$. Substituting $a = 0$ gives $f'(0) = -2(0) - 8 = -8$.

Compute f′(a)f ^ { \prime } ( a )f′(a) For a=0a = 0a=0

Compute $f ^ { \prime } ( a )$ For $a = 0$