diketahui f(x)=(3x-2)(x+1),nilai f(-2) adalah

f(x) = (3x-2)(x+1)
f(-2) = (3.(-2) - 2)((-2)+1)
= ((-6) - 2)(-1)
= (-8)(-1)
= 8

Langsung aja y

f(x) = (3x-2)(x+1)
f(x) = 3x² + 3x - 2x - 2
f(x) = 3x² + x - 2

f(-2) = 3(-2)² + (-2) - 2
f(-2) = 3(4) - 4
f(-2) = 12 - 4
f(-2) = 8

Semoga berguna +_+