已知2x-y=10,求{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y的值

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已知2x-y=10,求{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y的值

已知2x-y=10,求{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y的值
已知2x-y=10,求{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y的值

已知2x-y=10,求{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y的值
{(x²+y²)-(x-y)²+2y(x-y)}除以4y
=(x²+y²-x²+2xy-y²+2xy-2y²)÷(4y)
=(4xy-2y²)/(4y)
=(2x-y)/2
=5

[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y
=(2xy+2xy-2y^2)/4y
=(2x-y)/2
=5

{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y
=((x^2+y^2-x^2+2xy-y^2+2y(x-y)))/4y
=2y(2x-y)/4y
=(2x-y)/2
=10/2
=5

{(x的平方+y的平方)-(x-y)的平方加2y(x-y)}除以4y
={x^2+y^2-x^2-y^2+2xy+2y(x-y)}/4y
={2xy+2y(x-y)}/4y
=(4x-2y)/4
=2(2x-y)/4
=2×10/4
=5

5