Tìm tất cả các giá trị của tham số m để hàm số
nghịch biến trên
?
A.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167769336_images/obj2019262287645598167769336_img1.png)
B.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167939899_images/obj2019262287645598167939899_img1.png)
C.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167685951_images/obj2019262287645598167685951_img1.png)
D.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167113065_images/obj2019262287645598167113065_img1.png)
Đáp án và lời giải
Đáp án:A
Lời giải:Ta có
.
Để hàm số nghịch biến trên
thì
.
Vậy đáp án đúng là A.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167224578_images/obj2019262287645598167224578_img1.png)
![img2](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167224578_images/obj2019262287645598167224578_img2.png)
![img3](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167224578_images/obj2019262287645598167224578_img3.png)
![img4](https://cungthi.online/upload/questionbank3/eduquestion/2019262287645598167/obj2019262287645598167224578_images/obj2019262287645598167224578_img4.png)