10．已知30的x次方=2010,67的y次方=2010,则（2/x)+(2/y)=
问题描述：
10．已知30的x次方=2010,67的y次方=2010,则（2/x)+(2/y)=
答
x=lg2010/lg30
y=lg2010/lg67
(2/x)+(2/y)
=2lg30/lg2010+2lg67/lg2010
=2(lg30+lg67)/lg2010
=2lg(30*67)/lg2010
=2lg2010/lg2010
=2