Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is :
- (A)30
- (B)12.5
- (C)10
- (D)25✓ Correct
Answer: (D)
Solution
If the sector has radius and arc length , the fencing is , and the area is . Setting gives , hence , and the greatest area is sq. m.
JEE Main · 2017 · 02 Apr 2017 · Offline · Single correct option