Cho khai triển
. Giá trị của
bằng:
A.A.
.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049216117_images/obj2018190858131552049216117_img1.png)
B.B.
.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049392550_images/obj2018190858131552049392550_img1.png)
C.C.
.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049742480_images/obj2018190858131552049742480_img1.png)
D.D.
.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049773472_images/obj2018190858131552049773472_img1.png)
Đáp án và lời giải
Đáp án:A
Lời giải:Chọn A
.
Thay
vào
ta có: ![img5](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img5.png)
.
Vậy đáp án đúng là A.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img1.png)
![img2](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img2.png)
![img3](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img3.png)
![img4](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img4.png)
![img5](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img5.png)
![img6](https://cungthi.online/upload/questionbank3/eduquestion/2018190858131552049/obj2018190858131552049506928_images/obj2018190858131552049506928_img6.png)