2013 Beijing Question 2 Single-choice Differentiating 2013_北京 Paper 2.(5 分)设 $a$,$b$,$c\in\mathbb{R}$,且 $a>b$,则( ) A. $ac>bc$B. $\dfrac{1}{a}<\dfrac{1}{b}$C. $a^2>b^2$D. $a^3>b^3$ Answer keyD ☆ SaveCan't do it, show the explanation查看原卷 →