Question

The maximum value of $-x^2-8x+17$ is

• A. $17$`
• B. $-1$
• C. $33$
• D. $2$

Answer 1

Answer: (C)

$33$

$f\left(x\right)=-x^2-8x+17$

$f^{\prime }\left(x\right)=-2x-8=0$

$x=-4$

$f^{\prime }\left(x\right)=-2(-ve)$

$\therefore$ at $x=-4\to$ it will be a max.

$\therefore f\left(x\right)=-(-4{)}^2-8(-4)+17$

$=-16+32+17=33$.