2013 Zhejiang Question 3 Single-choice Differentiating 2013_浙江卷 (2013·理) 3.(5 分)(2013•浙江)已知 $\mathrm{x}, \mathrm{y}$ 为正实数,则( ) A. $2^{\lg x+\lg y}=2^{\lg x}+2^{\lg y}$B. $2^{\lg (\mathrm{x}+\mathrm{y})}=2^{\lg \mathrm{x}} \cdot 2^{\lg \mathrm{y}}$C. $2^{\lg x \bullet \lg y}=2^{\lg x}+2^{\lg y}$D. $2^{\lg (x y)}=2^{\lg x} \cdot 2^{\lg y}$ Answer keyD ☆ SaveCan't do it, show the explanation查看原卷 →