Question

What is f( 1) for the function given?f(x) = 3x + 811

Answer 1

the given expression i s

$f(x)=x^2-3x+8$

for f(-1) , put x = -1 in the equation.

$f(-1)=(-1)^2-3(-1)+8$

f(-1) = 1 + 3 + 8 = 12

so the answer is

f(-1) = 12