Engineering Board Exam Reviewer · Optimization (Maxima and Minima) · easy
Find two positive numbers whose sum is 20 and whose product is a maximum.
- 10 and 10
- 8 and 12
- 5 and 15
- 9 and 11
Answer
A. 10 and 10
Solution
Let y=20-x. Then P=x(20-x)=20x-x2. P'=20-2x=0 x=10, so y=10.
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