BÀI 3.    X M Y1 2

3 .2 3 .2 2 3 .3 3 .3 3 35m m m m m m      3m

²

3m 7 715m

2

15m 35 35      

2

m m3 ( 1) 0m m3 3 7 70m        

²

    13 3 14 0

Vậy m = 0 hoặc m = – 1