2.2.2对数与对数运算(2)一选择题1.的值是 ( )A. B.1 C. D.22.设,那么n的值是( )A.log B.log C.log D.log3103.2等于 ( )A.2+ B.2 C.2+ D.1+4.已知,那么等于 ( )A. -1 B.0 C.1 D.3二.填空题5.若loga=-2log37,则a=_6.化简(log23)(log34)(log45)(log56)(log67)(log78)=_ _7.已知lg2=a,lg3=b,则lg用a、b表示为_8.=三解答题9.计算: lg25+lg2+lg+lg(0.01)-110. 计算:2log32log3+log38511.