CBSE Class 12-science Answered

take first derivative of the expression

equate this to zero and find the values of variable

take second derivative

substitute the values of variable

if the outcome for any value is positive then this is point of minima

and by putting this point of minima in given expression minimum value of the expression can be obtained

if the outcome for any value is negative then this is point of maxima

and by putting this point of maxima in given expression maximum value of the expression can be obtained