设 a ， b ， c∈R ，且 a>b ，则下列选项中一定成立的是

题干

设 a ， b ， c∈R ，且 a>b ，则下列选项中一定成立的是（）

A： $a c > b c$

B： $\frac{1}{a} < \frac{1}{b}$

C： $a^{2} > b^{2}$

D： $a^{3} > b^{3}$

上一题下一题 0.0难度选择题更新时间:2019-03-18 10:08:42

D

阅读下列材料，从A、B、C、D四个选项中选出最佳答案，并把答题卡上对应题目的答案标号涂黑。

Don't do your homework alone when you find it difficult! TFK's Homework Helper has many useful tools with tips to help you do your homework better.

	A + Papers Do you need help with writing homework? Check out A + Papers! It will show you how to write eight different kinds of school papers. Get Started!
	Flash-card Maker Do you know the state capitals? Check yourself with TFK’s flash cards (抽认卡), or make your own flash cards to study for your next exam. Get Started!
	Writing Suggestions How do you write a good article to introduce yourself? Find answers to all of your writing questions here. Get Started!
	Grammar Talent Do you know how to use commas (逗号)? Are you a talent when it comes to big letter? Go over grammar rules, and then test yourself with Grammar Talent. Get Started!
	Writer's Toolbox Whether you need a dictionary or an electronic (电子的) machine which can change one language into another, we’ve got you covered here. Get Started!