Determine where the function is increasing and where it is decreasing.
-$$f ( x ) = x ^ { 2 } - 8 x$$
A) increasing on $( - \infty , 4 )$
decreasing on $( 4 , \infty )$

B) increasing on $( - \infty , - 4 )$
decreasing on $( - 4 , \infty )$

C) increasing on $( 4 , \infty )$
decreasing on $( - \infty , 4 )$

D) increasing on $( - 4 , \infty )$
decreasing on $( - \infty , - 4 )$

Question

Determine where the function is increasing and where it is decreasing.
-$$f ( x ) = x ^ { 2 } - 8 x$$
A) increasing on $( - \infty , 4 )$
decreasing on $( 4 , \infty )$

B) increasing on $( - \infty , - 4 )$ 
decreasing on $( - 4 , \infty )$

C) increasing on $( 4 , \infty )$
decreasing on $( - \infty , 4 )$

D) increasing on $( - 4 , \infty )$
decreasing on $( - \infty , - 4 )$

Quizplus · Accepted Answer

To determine where the function is increasing or decreasing, we first find its derivative: $f'(x) = 2x - 8$. Setting $f'(x) = 0$ gives $x = 4$. The function is decreasing where $f'(x) < 0$ (to the left of $x = 4$) and increasing where $f'(x) > 0$ (to the right of $x = 4$).

Determine Where the Function Is Increasing and Where It Is f(x)=x2−8xf ( x ) = x ^ { 2 } - 8 xf(x)=x2−8x

Determine Where the Function Is Increasing and Where It Is $f ( x ) = x ^ { 2 } - 8 x$