(1)原式=
=lg3
+lg23?lg103 2
3 2 lg
12 10
=
lg3+3lg2?3 2
3 2 lg(3×4)?1
=
(lg3+2lg2?1)3 2 lg3+2lg2?1
.3 2
(2)由18b=5得:log185=b,
log365=
=
log185
log1836
=
log185
log18(4×9)
=
log185 2log182+log189
=
log185 2(1?log189)+log189
.b 2?a