\(5,\\ a,=x^4+4x^2+4-4x^2=\left(x^2+2\right)^2-4x^2=\left(x^2-2x+2\right)\left(x^2+2x+2\right)\\ b,=x^4+16x^2+64-16x^2=\left(x^2+8\right)^2-16x^2=\left(x^2-4x+8\right)\left(x^2+4x+8\right)\\ c,=x^8+x^7+x^6-x^6+x^5-x^5+x^4-x^4+x^3-x^3+x^2-x^2+x-x+1\\ =x^6\left(x^2+x+1\right)-x^4\left(x^2+x+1\right)+x^3\left(x^2+x+1\right)-x\left(x^2+x+1\right)+\left(x^2+x+1\right)\\ =\left(x^6-x^4+x^3-x+1\right)\left(x^2+x+1\right)\)

\(d,=x^8+2x^4+1-x^4=\left(x^4+1\right)^2-x^4=\left(x^4-x^2+1\right)\left(x^4+x^2+1\right)\\ =\left(x^4-x^2+1\right)\left(x^4+2x^2+1-x^2\right)\\ =\left(x^4-x^2+1\right)\left(x^2-x+1\right)\left(x^2+x+1\right)\\ e,=x^5+x^4-x^4+x^3-x^3+x^2-x^2+x+1\\ =x^3\left(x^2+x+1\right)-x^2\left(x^2+x+x\right)+\left(x^2+x+1\right)\\ =\left(x^3-x^2+1\right)\left(x^2+x+1\right)\\ f,=x^3+2x^2-x^2-2x+2x+4\\ =\left(x+2\right)\left(x^2-x+2\right)\\ g,=x^4+2x^2+1-25=\left(x^2+1\right)^2-25\\ =\left(x^2+1-5\right)\left(x^2-1-5\right)=\left(x^2-4\right)\left(x^2-6\right)=\left(x-2\right)\left(x+2\right)\left(x^2-6\right)\)

\(h,=x^3-2x^2+2x^2-4x+2x-4=\left(x-2\right)\left(x^2+2x+2\right)\\ i,=a^4-4a^2b^2+4b^4-4a^2b^2=\left(a^2-2b^2\right)^2-4a^2b^2\\ =\left(a^2-2ab-2b^2\right)\left(a^2+2ab-2b^2\right)\)

Mình viết phần điền tiếp thui nhé, cái đề cho mk k viết

1 where they were organizing the party

2 if I knew the woman in red over there

3 Peter why he didn't turn off the light

4 she was going

5 if the nearest post office was far away

6 what we were going to do that Christmas

7 where I worked

8 how far it was from my house to my school

9 if his friend was a good person

10 how many people there were in my family

1. ...where they were organizing the party.

2. ...if I knew the woman in red over there.

3. ...Peter why he didn't turn off the light.

4. ...she was going.

5. ...if the nearest post office was far away.

6. ...what we were going to do this Christmas.

7. ...where I worked.

8. ...how far it was from my house to my school.

9. ...if his friend was a good person.

10. ...how many people there were in my family.

1. ...where they were organizing the party.

2. ...if I knew the woman in red over there.

3. ...Peter why he didn't turn off the light.

4. ...she was going.

5. ...if the nearest post office was far away.

6. ...what we were going to do this Christmas.

7. ...where I worked.

8. ...how far it was from my house to my school.

9. ...if his friend was a good person.

10. ...how many people there were in my family.

a: Xét tứ giác BHCK có 

BK//CH

BH//CK

Do đó:BHCK là hình bình hành

Độ dài cạnh đối diện với góc 30 độ là 9cm

14.D

15.B

16.C

d b c

a) Xét tứ giác ADHE có 

\(\widehat{ADH}\) và \(\widehat{AEH}\) là hai góc đối

\(\widehat{ADH}+\widehat{AEH}=180^0\left(90^0+90^0=180^0\right)\)

Do đó: ADHE là tứ giác nội tiếp(Dấu hiệu nhận biết tứ giác nội tiếp)