(x+1)^2-3y=3xy,x大于0,y大于0,则x+2y+1/x-y+1的值为
问题描述:
(x+1)^2-3y=3xy,x大于0,y大于0,则x+2y+1/x-y+1的值为
答
题目是否为(x+2y+1)/(x-y+1)
若是,则
由(x+1)^2-3y=3xy
得(x+1)^2=3y(x+1)
x大于0,
所以x+1=3y
代入(x+2y+1)/(x-y+1)=(3y+2y)/(3y-y)=5/2