数学分式已知1/x+1/Y=5,
解: ∵1/x+1/y=y/xy+x/xy=(x+y)/xy
∴(x+y)/xy=5
∴5xy=x+y
∵(2x-3xy+2y)/(x+2xy+y)=[2(x+y)-3xy]/(x+y+xy)
∴[2(x+y)-3xy]/(x+y+2xy)=(10xy-3xy)/(5xy+2xy)=7xy/7xy=1
∴已知1/x+1/Y=5,则分式2x-3xy+2y/x+2xy+y的值为1
。
解: ∵1/x+1/y=y/xy+x/xy=(x+y)/xy
∴(x+y)/xy=5
∴5xy=x+y
∵(2x-3xy+2y)/(x+2xy+y)=[2(x+y)-3xy]/(x+y+xy)
∴[2(x+y)-3xy]/(x+y+2xy)=(10xy-3xy)/(5xy+2xy)=7xy/7xy=1
∴已知1/x+1/Y=5,则分式2x-3xy+2y/x+2xy+y的值为1
。
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