已知X分之1+Y分之1=5,求X+2XY+Y分之2X-5XY+2Y的值

问题描述:

已知X分之1+Y分之1=5,求X+2XY+Y分之2X-5XY+2Y的值

∵1/x+1/y=5
∴(x+y)/(x*y)=5
∴x+y=5xy
所以(2x-5xy+2y)/(x+2xy+y)=(10xy-5xy)/(5xy+2xy)=5/7分子2x-5xy+y如何化为10xy-5xy详细回答你是2x-5xy+2y=2x+2y-5xy=2(x+y)-5xy=2*5xy-5xy=10xy-5xy=5xy