f(x) = (2x²-2x+1)akar8 maka f'=...? tolong dibantu yaa

f (x) = (2x^2 -2x +1)^8
f' (x) = 8(2x^2-2x+1)^7.(4x-2)
f' (x) = (32x - 16)(2x^2 -2x +1)^7
f'' (x) = (32)(2x^2-2x+1)^7+ (32x-16).7(2x^2-2x+1)^6.(4x-2)
f'' (x) = 32(2x^2-2x+1)^7 + 7(32x-16)(4x-2).(2x^-2x+1)^6.
f'' (x) = 32(2x^2-2x+1)^7 + 7(128x^2-128x+32)(2x^2 -2x +1)^6
f''' (x) = 7.32(2x^2-2x+1)^6(4x-2) + 7(256x^2-128)(2x^2-2x+1)^6 + 7(128x^2-128x+32).6(2x^2-2x+1)^5(4x-2)
f''' (1) = 224{2(1)^2-2(1)+1 }^6.(4.1-2) + 7(256(1)^2-128)(2.1^2-2.1+1)^6+7(128.1^2-128.1+32).6(2.1^2-2.1+1)^5(4.1-2)
= 224(2-2+1)^6.(4-2)+7(256-128)(2-2+1)^6+ 7(128-128+32).6.(2-2+1)^5(4-2)
= 224.2+7(128).1+7.32.6.1.2
= 448+ 896 + 2.688
= 4.072