Completing the square

Completing the square is a technique of elementary algebra wherein an expression

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:x^2+bx

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is replaced by one of the form

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:(x+c)^2+d.

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Specifically, we have

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:left(x^2+bx+(b/2)^2 ight)-(b/2)^2 = (x+(b/2))^2-b^2/4.

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See quadratic equation.

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