f（x）=log2|x-1|,
t=|x-1|≠0,y=log2t,
y=log2t,
f（x）=log2|x-1|,
t=|x-1|
t=|x-1|= x-1 x＞11-x x＜1 x＞1,
答案（1,+∞）
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