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If x + y = a and x тАУ y = b, then 2xy

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If x + y = a and x тАУ y = b, then 2xy [#permalink]

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18 Feb 2004, 11:00
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If x + y = a and x тАУ y = b, then 2xy =
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18 Feb 2004, 12:32
2xy = a power 2 - (x power 2 + y power 2 )
or
2xy = (x power 2 + y power 2) - b power 2
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18 Feb 2004, 12:49
x + y = a
x тАУ y = b

2x=a+b x=a+b/2
2y = a-b y=a-b/2

2xy =(a+b/2) * (a-b/2)
2xy = 2/4((a+b)*(a-b))

2xy = 1/2(a^2-b^2)

Vivek.
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18 Feb 2004, 13:06
I got the same...a^2 -b^2/2
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shubhangi

18 Feb 2004, 13:06
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If x + y = a and x тАУ y = b, then 2xy

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