Question

the value of (x+y)²+(x-y)²-2(x²+y²)
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Answer 1

Step-by-step explanation:

$({x + y)}^{2} + ({x - y)}^{2} - 2( {x}^{2} + {y}^{2} ) \\ {x}^{2} + {y}^{2} + 2xy + {x}^{2} + {y}^{2} - 2xy - 2 {x}^{2} - 2 {y}^{2} \\ {x}^{2} + {y}^{2} + {x}^{2} + {y}^{2} - 2 {x}^{2} - 2 {y}^{2} \\ 2 {x}^{2} + 2 {y}^{2} - 2 {x}^{2} - 2 {y}^{2} \\ 0$