log3 2=a 那么log24 0.25=?
问题描述：
log3 2=a 那么log24 0.25=?
答
log24 0.25
=log24 (1/4)
=-log24 4
=-(log3 4)/(log3 24)
=-(2log3 2)/[log3 (3*8)]
=-2a/(log3 3+log3 8)
=-2a/(1+3log3 2)
=-2a/(3a+1)