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计算:(1)log37•log73;(2)log225•log38•log59;(3)3log23•log34•log45•log52.

题目详情
计算:(1)log37•log73;
(2)log225•log38•log59;
(3)3log23•log34•log45•log52.
▼优质解答
答案和解析
(1)log37•log73=log37•
1
log37
=1.
(2)log225•log38•log59=
2lg5•3lg2•2lg3
lg2lg3lg5
=12;
(3)3log23•log34•log45•log52=3
lg3•2lg2•lg5•lg2
lg2•lg3•2lg2•lg5
=3.