Find maximum or minimum values of the functions y=25x2+5-10x

For maximum and minimum value, we can put dydx=0dydx=50x-10=0x=15Further,d2ydx2=50or d2ydx2 has positive value at x=15, Therefore, y has minimum value at x=15.Substituting  x=15 in given equation, we getymin=25152+5-1015=4