问题
解答题
(1)用配方法解方程:2y2-4y=2;
(2)解方程:2(x-1)2-5(x-1)+2=0.
答案
(1)2y2-4y=2,
2y2-4y-2=0,
y2-2y-1=0,
(y-1)2-2=0,
(y-1)2=2,
y-1=±
,2
解得:y1=
+1,y2=-2
+1;2
(2)2(x-1)2-5(x-1)+2=0,
(x-1-2)[2(x-1)-1]=0,
故(x-3)=0或(2x-3)=0,
解得:x1=3,x2=
.3 2