For $f(x) = x^{3} + 2 x^{2} - x$, what is $f''(1)$?

Explanation

1. 01

   $f'(x) = 3 x^{2} + 4 x - 1$ and $f''(x) = 6 x + 4$.

2. 02

   So $f''(1) = 10$.