这个配方对不对啊,人才请进来

来源:百度知道 编辑:UC知道 时间:2024/05/30 14:36:14
2x²-4x+6=0
2[x²-2x+3]=0
2[(x-1)²+1-1+3]=0
2[(x-1)²+3]=0

2x²-4x+6=0
2[x²-2x+3]=0
2[(x-1)²-1+3]=0
2[(x-1)²+2]=0
2(x-1)²+4=0

2x²-4x+6=0 两边同时除2
x²-2x+3=0
(x-1)²+1+3=0
(x-1)²+4=0

第三步错了!应该是这样:2[(x-1)²-1+3]=0;2[(x-1)²+2]=0

2x2-4x+6=0

2[x2-2x+3]=0

2[(x-1)2+1-1+3]=0 <-错了 因为(x-1)2 = x2 -2x +1 所以2〔(x-1)2-1+3〕= 0

2[(x-1)2+3]=0 -> 2[(x-1)2+2]=0 -> (x-1)2+2 = 0

2[(x-1)2 + 2] = 0