Find the derivative of π f(x)=3x²-6x+74x-1 π.
a) π 3(4x-1)-12x(3x²-6x+7)(4x-1)² π
b) π 3(4x-1)-12x(3x²-6x+7)(4x-1) π
c) π 12x(3x²-6x+7)-3(4x-1)(4x-1)² π
d) π 12x(3x²-6x+7)-3(4x-1)(4x-1) π