Answer :

x+y=8 y=8-x

xy=x(8-x)


Let f(x)=8x-x2


Differentiating f(x) with respect to x, we get


f’(x)=8-2x


Differentiating f’(x) with respect to x, we get


f’’(x)=-2<0


For maxima at x=c, f’(c)=0 and f’’(c)<0


f’(x)=0 x=4


Also f’’(4)=-2<0


Hence, x=4 is a point of maxima for f(x) and f(4)=16 is the maximum value of f(x).

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :

If the sum of theMathematics - Board Papers

A metal box with Mathematics - Board Papers

Show that aRD Sharma - Volume 1

Find the local maMathematics - Board Papers

Prove that the seMathematics - Board Papers

Prove that the raMathematics - Board Papers

Prove that the leMathematics - Board Papers