A Level Maths Notes: C1 - Minima and Maxima of Quadratics
To find the minimum or maximum of a quadratic we
complete the square expressing the function in the form
If
the
minimum will be where
so
and
the minimum is at
If
the
maximum will be wheresoand
the maximum is at
For example, to find the minimum of
complete
the square to get
then
the minimum is at
To find the maximum of
complete
the square to get
then the maximum is at