Find the derivative of the function f(x) = x^3 - 4x^2 + x + 1.
Correct: A
The derivative of x^n is n*x^(n-1). Applying this rule, the derivative of x^3 is 3x^2, the derivative of -4x^2 is -8x, the derivative of x is 1, and the derivative of 1 is 0. Combining these gives f'(x) = 3x^2 - 8x + 1.