2013 Zhejiang Question 3 Single-choice Differentiating 2013_浙江卷 (数学) 3. (5分) (2013•浙江)已知x,y为正实数,则( ) A. $2lgx+lgy=2lgx+2lgy$B. 2lg(x+y)=2lgx•2lgyC. 2lgx•$lgy=2lgx+2lgy$D. 2lg(xy)=2lgx•2lgy Answer keyD ☆ SaveCan't do it, show the explanation查看原卷 →