log3 2+log3 1/2 +lg20 +lg5等于多少
问题描述:
log3 2+log3 1/2 +lg20 +lg5等于多少
答
log3 2+log3 1/2 +lg20 +lg5
=log3 (2*1/2) +lg(20 *5)
=log3 1 +lg100
=0+2
=2