Engineering Board Exam Reviewer · Optimization (Maxima and Minima) · medium
Find the maximum area of a rectangle that can be inscribed in a circle of radius 4.
- 32
- 16
- 64
- 24
Answer
A. 32
Solution
Let the rectangle have half-sides x,y with x2+y2=16. Area =4xy, maximized when x=y=4/ 2=2 2, giving Area =4(2 2)(2 2)=32.
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