Question

Over what interval is the graph of f(x) = -(X + 8)2 - 1 decreasing?
(-8,infinity)
(8,infinity )
(-infinity ,8)
(-infinity ,-8)

Answer 1

Answer:

Function is decreasing on (-8,infinity)

Step-by-step explanation:

The given function is $f(x)=-(x+8)^2-1$

The first derivative is given by

$f'(x)=-2(x+8)$

For the function to be decreasing, we have

$f'(x)<0\\\\-2(x+8)<0$

Divide both sides by -2. Since, we are dividing by a negative number hence, the inequality sign will change.

$(x+8)>0$

Subtract 8 to both sides

$x>-8$

Therefore, the function is decreasing on (-8,infinity)

First option is correct.

Answer 2

Answer:

A.-8,infinity

Step-by-step explanation:

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