Question

Find f ''(x) when f(x) = x^2 sin x

Answer 1

Wolfram says:-

http://www.wolframalpha.com/input/?i=second+derivative+of+x^2sinx

Answer 2

Use the 1D2 + 2D1 method.

Split it into parts.

The first part is x^2

The second part is sin x

So take 1D2 + 2D1 to get the first derivative.

(x^2)(cos x) + (sin x)(2x)

Repeat to get the second derivative.