Algebraic Constraint Math Example 4

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Example 4

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If x+y=10x + y = 10 and x,y>0x, y > 0, what is the maximum of xyxy?

Solution

  1. 1
    By AM-GM: x+y2โ‰ฅxy\frac{x+y}{2} \geq \sqrt{xy}, so 5โ‰ฅxy5 \geq \sqrt{xy}, giving xyโ‰ค25xy \leq 25.
  2. 2
    Maximum at x=y=5x = y = 5: xy=25xy = 25.

Answer

xy=25xy = 25 when x=y=5x = y = 5.
The constraint x+y=10x + y = 10 limits the possible products xyxy. The AM-GM inequality shows that the product is maximized when the values are equal โ€” a powerful optimization principle.

About Algebraic Constraint

A mathematical condition expressed as an equation or inequality that restricts which values the variables are allowed to take.

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