Given f(x)=2x^3 - 2x^2 + 8x, find f'(x) and f"(x).

The first step in scoring full marks on this typically 4 mark question is to recognise what it's asking you to do. We use the process of differentiation to solve it. f(x)=2x^3 - 2x^2 + 8xf'(x) = 6x^2 - 4x + 8 as we multiply coefficients by the corresponding power of x and then reduce the power by 1. This also leaves the final term as a constant term without an x. The general rule we use is f'(x) = (na)x^(n-1) where our original equation has the form f(x) = ax^n.Using a similar method for f"(x) where the question asks us to differentiate again to find the second derivative, we find f"(x) = 12x - 4.

Related Maths A Level answers

All answers ▸

How do i solve two linear simultaneous equations 2x+y=7 & 3x-y=8 ?


Given that Sin(A) = 1/sqrt(3), show that Tan(A) = 1/sqrt(2)


Where z is a complex number, what is the cartesian form of |Z-2+3i| = 1?


If cos(x)= 1/3 and x is acute, then find tan(x).