3^a=2则log3(8)-2log3(6)等于多少
问题描述：
3^a=2则log3(8)-2log3(6)等于多少
答
3^a=2 两边同时用log3
a=log3(2)
log3(8)-2log3(6)
=log3[（2）3]-2log3(2*3)
=3log3(2)-2[log3(2)+1]
=3a-2a-2
=a-2
答
3^a=2→log3(2)=a
log3(8)-2log3(6)=3log3(2)-2log3(2)-2log3(3)=log3(2)-2=a-2