Trong không gian với hệ trục tọa độ
, cho hai mặt phẳng
và
lần lượt có phương trình là
,
và điểm
. Tìm phương trình mặt phẳng
đi qua điểm
đồng thời vuông góc với hai mặt phẳng
,
.
A.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221834965_images/obj20195011643718249221834965_img1.png)
B.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221754514_images/obj20195011643718249221754514_img1.png)
C.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221925076_images/obj20195011643718249221925076_img1.png)
D.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221671128_images/obj20195011643718249221671128_img1.png)
Đáp án và lời giải
Đáp án:B
Lời giải:Phân tích:
Vectơ pháp tuyến của
là
.
Vectơ pháp tuyến của
là
.
Vì
vuông góc với
và
nên
có vectơ pháp tuyến là
.
Mặt phẳng
có phương trình là
hay
.
![img1](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img1.png)
![img2](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img2.png)
![img3](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img3.png)
![img4](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img4.png)
![img5](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img5.png)
![img6](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img6.png)
![img7](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img7.png)
![img8](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img8.png)
![img9](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img9.png)
![img10](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img10.png)
![img11](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img11.png)
![img12](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img12.png)
![img13](https://cungthi.online/upload/questionbank3_20201220/eduquestion/20195011643718249221/obj20195011643718249221637201_images/obj20195011643718249221637201_img13.png)