Let
For max or min put
..i.e
. If then is point of minima and if then is point of maxima
ALITER
Obviously, if
if
Well, we know that a quadratic function is a MIN when the coefficient of x^2 is positive and a MAX when the coefficient of x^2 is negative. Is there a particular proof or derivation for this? What is the reasoning behind it?
Thanks in advance.