已知lg2=a,lg3=b,求下列各式的值 (1)lg6 (2)log3|4 (3)log2|12 (4)lg3/2

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已知lg2=a,lg3=b,求下列各式的值 (1)lg6 (2)log3|4 (3)log2|12 (4)lg3/2
已知lg2=a,lg3=b,求下列各式的值 (1)lg6 (2)log3|4 (3)log2|12 (4)lg3/2

已知lg2=a,lg3=b,求下列各式的值 (1)lg6 (2)log3|4 (3)log2|12 (4)lg3/2
(1)lg6=lg2+lg3=a+b (lgab=lga+lgb)
(2)log3|4=lg4/lg3=2lg2/lg3=2a/b (loga|b=lgb/lga lga^n=nlga)
(3)log2|12=lg12/lg2=(lg4+lg3)/lg2=(2a+b)/a=2+b/a
(4)lg3/2=lg3-lg2=b-a (lgb/a=lgb-lga)