Tập nghiệm của bất phương trình
là
A. A.
.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476541818_images/obj2020011573748235476541818_img1.png)
B. B.
.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476306266_images/obj2020011573748235476306266_img1.png)
C. C.
.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476718181_images/obj2020011573748235476718181_img1.png)
D. D.
.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476532088_images/obj2020011573748235476532088_img1.png)
Đáp án và lời giải
Đáp án:A
Lời giải: Lời giải
ĐK
.
Ta có
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476503961_images/obj2020011573748235476503961_img1.png)
![img2](https://cungthi.online/upload/questionbank3_20201220/eduquestion/2020011573748235476/obj2020011573748235476503961_images/obj2020011573748235476503961_img2.png)