求发个图啊,看着真心累~要不你去文档写好了截图也好啊(x+y)/(√x-√y)-2xy/(x√y+y√x)(x+y)/(√x-√y)=(x+y)(√x+√y)/(x-y)2xy/(x√y+y√x)=2√xy/ (√x+√y) =2√xy (√x-√y)/(x-y)(x+y)/(√x-√y)-2xy/(x√y+y√x)=(x+y)(√x+√y)/(x-y) -2√xy (√x-√y)/(x-y)=(x+y)(√x+√y) -2√xy (√x-√y) /(x-y)x-8≥0 x≥88-x≥0x≤8所以 x=8此时 y=18=(x+y)(√x+√y) -2√xy (√x-√y) /(x-y) =26×(√8+√18) -2√144(√8-√18) / (-10)最后答案自己就能算出来了~