下列命题中的假命题是_刷题宝

题干

下列命题中的假命题是（）

A：∃x∈R，lgx＞0

B：∃x∈R，sinx=1

C：∀x∈R，x²＞0

D：∀x∈R，2^x＞0

上一题下一题 0.0难度选择题更新时间:2017-12-25 02:01:47

答案(点此获取答案解析）

C

同类题1

Her handbag is on her desk. She ____ back home.

同类题2

阅读短文，判断下列句子是否符合短文内容，符合的写正确，不符合的写错误。

Jim lives in a city with his wife. He is a police officer. He works in a police. It is not far from his home, so he goes to work on foot every day. His wife is a worker, she works in a factory. It's far from her home, she goes to work by car. When she drives the car, she is very careful. When the light is red, she stops. When the light is yellow, she waits. She won't go until the light is green. She always says that we must obey (遵守)the traffic rules.

同类题3

如图是某电炖锅电路的简化原理图，R₁和R₂均为发热电阻，R₂的阻值是123.2Ω，电源电压是220V．电炖锅有“烹煮”和“慢炖”两个档位，“烹煮”功率是500W．在一次煮汤过程中，按下开关连接a点，进行“烹煮”，20min后开关自动跳起连接b点，进行“慢炖”再过50min后电炖锅自动断电．试求：

同类题4

烧杯中有一定质量的MgO和MgCO₃的混合物，向其中加入150g稀盐酸，恰好完全反应，一定温度下，得到156g不饱和溶液．下列数据中，与该溶液的溶质质量分数最接近的是（）

同类题5

go, to, can't, I, school, today(.)
____

小学学科试题库

初中学科试题库

高中学科试题库