II Grammar and....

choose the correct answer

3.D

4.A

5.B

6.C

7.C

8.C

C.Reading

read the...

1.B

2.C

3.D

4.B

3.D

4.A

5.B

6.C

7.C

8.C

Tôi còn thức lâu

Trang 1:

1)

1. C

2. D

2)

3. D

4. A

5. B

6. C

7. A

8. C

3)

1. B

2. C

3. A 

4. B

Trang 2

4)

D, B, A, C

5)

1. How far from Vinh Phuc to Ha Noi city.

2. I used to walk to school when I was a student.

3. In spite of the short, they still .....

4. This building has built in 19....

6)

1. How far is it from Phuc .... to Ha .... ?

2. When you went with your parent last year?

3. When the flower festival is celebrated?

4. Whose picture are there?

\(A\left(x\right)+B\left(x\right)=3x^4-4x^3+2x^2-3+8x^4+x^3-9x+\dfrac{2}{5}\)

\(=11x^4-3x^3+2x^2-9x-\dfrac{13}{5}\)

\(A\left(x\right)-B\left(x\right)=3x^4-4x^3+2x^2-3-8x^4-x^3+9x-\dfrac{2}{5}\)

\(=-5x^4-5x^3+2x^2+9x-\dfrac{17}{5}\)

\(B\left(x\right)-A\left(x\right)=8x^4+x^3-9x+\dfrac{2}{5}-3x^4+4x^3-2x^2+3\)

\(=5x^4+5x^3-2x^2-9x+\dfrac{17}{5}\)

\(A\left(x\right)+B\left(x\right)=11x^4-3x^3+2x^2-9x-\dfrac{13}{5}\)

\(A\left(x\right)-B\left(x\right)=-5x^4-5x^3+2x^2+9x-\dfrac{17}{5}\)

\(B\left(x\right)-A\left(x\right)=5x^4+5x^3-2x^2-9x+\dfrac{17}{5}\)

a) Ta có: \(P\left(x\right)=3x^5-2x^4-2x^5-2x^2-x+3x^2+2\)

\(=x^5-2x^4+x^2+2\)

Ta có: \(Q\left(x\right)=x^5+8-5x+3x^3+3x+x^4-4x^5\)

\(=-3x^5+x^4+3x^3-2x+8\)

b) \(P\left(x\right)+Q\left(x\right)=x^5-2x^4+x^2+2-3x^5+x^4+3x^3-2x+8\)

\(=-2x^5-x^4+3x^3+x^2-2x+10\)

\(P\left(x\right)-Q\left(x\right)=x^5-2x^4+x^2+2+3x^5-x^4-3x^3+2x-8\)

\(=4x^5-3x^4-3x^3+x^2+2x-6\)

không có mẹo gì cả, chỉ có cần bạn ôn thì làm bài sẽ tốt thôi ^^

nên cầm theo bảng tuần hoàn :>

cóp phao ạ 

Ta có: \(\left(x^{3n}+y^{3n}\right)\left(x^{3n}-y^{3n}\right)=-x^{6n}-y^{6n}\)

\(\Leftrightarrow x^{6n}-y^{6n}=-x^{6n}-y^{6n}\)

\(\Leftrightarrow n\in\varnothing\)