X≠ 1 and x >；; 0

The domain is (0, 1)( 1, positive infinity).

(2)lg(x-3)>0，x-3 & gt； 0

X>4 and x> III of the solution

The domain is (4, positive infinity)

(3) 16-4^x>； 0

x & lt2

The domain is (negative infinity, 2)

(4)x- 1 >0，3-x & gt； 0

1

The domain is (1, 3)