用换底公式1/log5(19)=log5(5)/log5(19)=log19(5)2/log3(19)=log3(9)/log3(19)=log19(9)3/log2(19)=log19(8)1/log5(19)+2/log3(19)+3/log2(19) =log19(22)同理1/log2（派）+2/log5（派）=logπ（29）所以后面的式子...