y=1/[log2(x2-4x+3)]的定义域 log2(x2-4x+3)≠0 and x2-4x+3>0x2-4x+3≠1 x2-4x+3>0x2-4x+2≠0 x2-4x+3>0x≠2+√2 and x≠ 2-√2 and( x3)定义域为（-∞,2-√2)∪(2-√2,1)∪(3,2+√2)∪ (2+√2,+ ∞)...