CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Among all sectors of a fixed perimeter, choose the one with maximum area. Then the angle at the center of this sector (i.e., the angle between the bounding radii) is
 


Solution

The correct option is C


Perimeter=2r+rθ=k (const.)Area=θ2r2=12(k2r)rA=12(kr2r2)dAdr=12(k4r)=0r=k4
d2Adr2 < 0
Now,2r+rθ=kk2+kθ4=kθ=2

flag
 Suggest corrections
thumbs-up
 
0 Upvotes



footer-image