giải pt

x³-15x²+78x-141=5∛2x-9

cho tập hợp A(a,8-a) tìm a để A có đọ dài bằng 5

lập bảng biến thiên và vẽ đồ thị hàm số  

a) y=\(\left\{{}\begin{matrix}\dfrac{1}{2}\left(x+3\right)^2\left(x\le1\right)\\2\left(x>1\right)\end{matrix}\right.\)

(m-1)x^2-2mx+m-2=0

a)Tìm m để pt có 2 nghiệm trái dấu 

b) tìm m để pt có nghiệm dương phân biệt

(m-1)x^2-2mx+m-2=0

cho bpt (x +1)(x+  2m )>0

tìm m để tập nghiệm của bpt chứa (1;+∞)

Present perfect simple and present perfect progressive
1. I ________ (clean) the house all day so I feel tired.
2. She ________(not buy) any new clothes for years.
3. My hands are dirty because I________ (garden)
4. We________ (wait) for hours but she________ (not arrive) yet.
5. Since Christmas she ________(write) to me twice
6. They________ (live) in Ho Chi Minh City since 1970.
7. You can't talk to John because he________ (go) out.
8. Mr. Robinson________ (teach) ill this school for fifteen years.
9. My hand is tired because I ________(write) letters all morning.
10. They ________ (see) that film before so they don't want to see it again.
11. How long________ you ________ (know) Mike? - I (know) ________ him since we were in secondary school.
12. They________ (build) the house next door for month. we have not finished yet.
13.You ________ (study) for five straight house.
14. Mark ________ (run) very fast and is out of breath now.
15. He ________ ( play ) for the school team in 25 matches so far

A=\(\dfrac{\sqrt{X}+1}{\sqrt{X}-1}\)

Timf x nguyên để A nguyên

hình như sai đề