已知X分之1-Y分之1=5,求X-2XY-Y分之2X+5XY-2Y的值+1的值,是这个分式后面+1哟

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已知X分之1-Y分之1=5,求X-2XY-Y分之2X+5XY-2Y的值+1的值,是这个分式后面+1哟

已知X分之1-Y分之1=5,求X-2XY-Y分之2X+5XY-2Y的值+1的值,是这个分式后面+1哟
已知X分之1-Y分之1=5,求X-2XY-Y分之2X+5XY-2Y的值+1的值,是这个分式后面+1哟

已知X分之1-Y分之1=5,求X-2XY-Y分之2X+5XY-2Y的值+1的值,是这个分式后面+1哟
1/x-1/y=5
(y-x)/xy=5
y-x=5xy
(2x+5xy-2y)/(x-2xy-y)+1
=[5xy+2(x-y)]/[(x-y)-2xy]+1
=-5xy/(-7xy)+1
=5/7+1
=12/7

(2x+5xy-2y)/(x-2xy-y)+1
=(2/y+5-2/x)/(1/y-2-1/x)+1
=[5-2(1/x-1/y)]/[-2-(1/x-1/y)]+1
=(5-10)/(-2-5)+1
=5/7+1
=12/7第2步甚么意思?分子分母同时除以xy可已把步骤写详细点吗?最好有批语=(2/y+5-2/x)/(1/y-2-1/x)+1 ...

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(2x+5xy-2y)/(x-2xy-y)+1
=(2/y+5-2/x)/(1/y-2-1/x)+1
=[5-2(1/x-1/y)]/[-2-(1/x-1/y)]+1
=(5-10)/(-2-5)+1
=5/7+1
=12/7

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