Engineering Board Exam Reviewer · Optimization (Maxima and Minima) · easy
A wire 36 cm long is bent to form a rectangle. Find the dimensions of the rectangle with maximum area.
- 9 cm x 9 cm
- 12 cm x 6 cm
- 10 cm x 8 cm
- 6 cm x 6 cm
Answer
A. 9 cm x 9 cm
Solution
l+w=18. Area =lw=l(18-l). d( Area)dl=18-2l=0 l=9=w: a square.
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