The second <derivative> is $y''=6x$, so $y''(1)=6>0$. By the <second-derivative test>, the <stationary point> is a \b[strict <local minimum>], at $(1,5)$. It is not a global minimum, since this cubic is unbounded below toward negative infinity.

Solution

Past exam of the mathematics course of the year 1 of the natural sciences course of the University of Cambridge / 2014 / Paper 1 / 8 / b / Solution

 Solution (source code)