对数:log(4)8-log(1/9)3 求值
问题描述:
对数:log(4)8-log(1/9)3 求值
答
log(4)8-log(1/9)3
=lg8/lg4-lg3/lg1/9
=lg2×4/2lg2-lg3/(-2×lg3)
=4/2+1/2
=5/2