Answer:
97
Step-by-step explanation:
First find the value of f'(x) then replace x with a.
f(x) = 6x² + x
using the derivative:
[tex] \boxed{ \mathfrak{\blue{f'(x) = n( {x}^{n - 1} )} } } [/tex]
[tex] \boxed{ \red{ \mathfrak{if \: f(x) = {x}^{n} } } } [/tex]
[tex]f'(x) = 6 ( {2x})^{(2 - 1)} + 1(x ^{1 - 1} )[/tex]
f'(x) = 6(2x) + 1
f'(x) = 12x + 1
now replace x with a which is said to be 8
f'(a) = 12× 8 + 1
f'(x) = 96 + 1
f'(x) = 97
