Sửa đề: Với a<=m<b thì tập hợp A giao F khác tập rỗng

Để A\(\cap\)F=∅ thì \(\left[\begin{array}{l}2m+9<0\\ 2m-1\ge5\end{array}\right.\Rightarrow\left[\begin{array}{l}2m<-9\\ 2m\ge6\end{array}\right.\Rightarrow\left[\begin{array}{l}m<-\frac92\\ m\ge3\end{array}\right.\)

=>Để A giao F khác rỗng thì \(-\frac92\le m<3\)

=>a=-9/2; b=3

\(P=2a+5b=2\cdot\frac{-9}{2}+5\cdot3=-9+15=6\)

I. Exercise1: Hãy chọn phương án thích hợp để điền vào chỗ trống.

1. This is…………..…my…... (my/I) book and that is………your... (your/ you) book.

2. Music is…………my….……..(I/ my) favorite subject.

3……I…(I/ My) want to be a teacher and…my.. (my/ me) sister wants to be a doctor.

4. Mai likes English but……………her……….. (her/ she) brother doesn’t.

5. They ………are………(is / are) very nice and friendly.

б. Hoa’s pencil case …is….(is/ are) blue.  (Her/ She) …her…friends’ pencil cases are violet.

7.Those students……are…….( are / is) very heavy.

8. What is………your…. (your/ you) father’s job?...........he.......(He/ His) is an engineer.

9. How old……is…. (are/ is)…your… (your/ you) sister…she…(She/ Her) is ten years old

10. These are my sister room. (They/it) They are very nice

1. getting
2. cooks
3. is playing
4. will come
5. is going to rain
6. to look
7. to pay
8. watch

\(sin^2x+cos^2x=1\)

=>\(cos^2x=1-\left(\dfrac{2}{3}\right)^2=1-\dfrac{4}{9}=\dfrac{5}{9}\)

mà \(cosx>0\)(Vì \(x\in\left(0;\dfrac{\Omega}{2}\right)\))

nên \(cosx=\sqrt{\dfrac{5}{9}}=\dfrac{\sqrt{5}}{3}\)

đề bài đâu hả bạn ?

I went to+place

a. is opened

b. was being pulled down

c. had been cleaned

d. Has the rubbish been collected