tìm a để a+17 và a-72 đều là số chính phương

tìm n thuộc N để

n^2+17 là số chính phương

n^2+18n+2020 là số chính phương

2n+17 là số chính phương

cho a,b,c thuộc Z thoã mãn a+b+c=0

cmr a^5+b^5+c^5 chia hết cho 5abc

1 phân thức đa thức sau thành nhân tử

a, A=(a+b+c)^2+(a-b+c)^2-4b^2

b, B=a*(b^2-c^2)-b*(c^2-a^2)+c*(a^2-b^2)

bài 2 phân thức đa thức sau thành nhân tử

a, A=(ab-1)^2+(a+b)^2

b, B=x^3-4x^2+12x-27

c, C=x^3+2x^2+2x+1

d, D=x^4-2x^3+2x-1

e, E=x^4+2x^3+2x^2+2x+1

f, F=x^2*(x^2-6)-x^2+9

m, M=(x^2+4y^2-5)^2-16*(x^2*y^2+2xy+1)

k, K=a^5-b^5-(a+b)^5

viết lại câu sao cho nghĩa ko đổi

1 I am reading a novel by Jack london right now

= A novel

2 When did you start to play the piano ?

= How long

3 Nobody helped him with what exercise

= he did

4 She drove too carelessly to avoid the accident

= She didn't

5 Minh is better at chemistry than hung (as)

= Hung isn't

6 I need 500 grams of beef (a)

= I need

7 Mai hasn't seen her grandparents for over 3 weeks (last)

= It's

8 She is used to walking home after school (habit)

= She is in

cho dạng đúng của từ trong ngoặc

1 lunar new year is one of the .... festivals in viet nam (tradition)

2 ...... , those students know how to keep the environment unpolluted (luck)

3 the distance from your house to school is much .... than i thought (long)

4 my nephew loves talking part in the outdoor ... after school (act)

5 it's a nice shop and the assistants here are all polite and very .... (help)

6 most of them think that Mr.John is an .... person (interest)

7 nowadays, women tend to want to lose .... (weigh)

8 at first , she got very angry but later she apologized for her ...... (patient)