若logx表示log10x(10为底数),且log - 知识问答

若logx表示log10x(10为底数),且log(5x^2)=a,则log(4/x^2)=

1个回答

log(5x^2)=a
log5+logx^2=a
logx^2=a-log5
log(4/x^2)
=log4-logx^2
=log4-a+log4
=lig20-a

相关问题