作业帮若X+3Y=0,XY≠0 求X²-3XY/XY+Y²的值
来源：学生作业帮助网 编辑：作业帮 时间：2024/07/10 14:30:56
x){ѽ4B8@'"Qg"ԊK u#"#"#!Z6I*']~
vUhW()TW@&Xi{m4*t+*55**+4z鄖3<ٱ
(a4@ ̈Շh*<ٽiR$Au!4P1P!TNF 1A z6
若X+3Y=0,XY≠0 求X²-3XY/XY+Y²的值
若X+3Y=0,XY≠0 求X²-3XY/XY+Y²的值
若X+3Y=0,XY≠0 求X²-3XY/XY+Y²的值
x+3y=0 => x=-3y => x/y=-3
原式= (x^2-3xy)/(xy+y^2) 上下各除个y^2
= [(x/y)^2-3(x/y)]/[(x/y)+1] 代入x/y=-3
= [(-3)^2-3(-3)]/[-3+1]
= -9