Jika f'(x)=6x-2 dan -4, nilai f(3)+2f(1)=…

F'(x) = 6x – 2
f(x) = 3x² – 2x
maka
f(3) + 2f(1)
= (3(3)² – 2(3)) + 2.(3(1)² – 2(1))
= (27 – 6) + 2.(3 – 2)
= 21 + 2
= 23