\(20\times20=400\)

Kết quả là :

23424 + 3421 = 26845 .

Ai thấy mình làm đúng thì k cho mình nha !

a, 4x³ -12x² + 9x

=x(4x² -12x + 9)

=x((2x)² - 2.3.2x + 3²)

=x(2x - 3)²

b,ab + c² -ac - bc

=(ab - ac) + (c² - bc)

=a(b - c) + c(c - b)

=a(b - c) - c(b - c)

=(a - c)(b - c)

c,4x² - y² + 1 - 4x
=((2x)² - 2.2x + 1) - y²

=(2x - 1)² - y²

=(2x - y -1)(2x + y - 1) 

d,6x² - 7x - 20

= -(-6x² + 7x + 20)

= -(-6x² + 11x +10 + 10 - 4x)

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

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

= -(3x + 2)(-2x + 5) - 2(-2x + 5) 

= -(-2x + 5)(3x + 4)

Các số nguyên đó là: -+9; -+8; -+7; -+6; -+5; -+4; -+3; -+2; -+1; 0

=>Tổng tất cả số nguyên đó là: 0

                 Đáp số: 0

Mong các bạn k cho mk

II. Viết lại câu

1.What a pity we are busy with doing our assignmets

-->We wish...... .................................................

2.Lan doesn't have keys to unlock doors

-->Lan wishes......... .. ........ . ..................

3.I'm sorry I don't know her address

I wish..... ................................................

4.Nam would like his father to give up playing gamble

-->Nam wishes....... . . ...............................................................

II. Chia động từ

1.Be quiet!The baby(sleep) ....... ......

2.The sun(set).. ... ...... in the West

3.Mrs. Doris White was cooking in the kitchen when I(come)................

4.The childrent(play).............. .when their teacher got into the room

5.The car(stop). ... ... . ..and the driver got off

6.I wish today(be)... ..... ....a holiday

7.We wish we(can)..... .. .. . ...leave here before noon

8.They wish(not be)... ............busy this afternoon

9.Jane wishes she(meet) her old friends in Hue again

10.My parents wish they(have)................a trip abroad

11.I(not see)... ......... her since last week

III. Chuyển những câu sau sang câu gián tiếp

1.He said to her"You are my friend"

-->He said to her... .. .. ............. .....

2.Johnny said to his mother"I don't know howto do this exercise"

Johnny told his mother...... ... ... ......... . .................

3."Don't come back before one o'clock"advised my brother

-->My brother advised me.. ...... ...........................................

4.My friend said"Are you going to leave tomorrow? "

-->My friend asked me... .... .. .... .. . .... ....... ............ . ...

5."Have you done your homework? "Said my mother

-->My mother asked me.. ........................................................

6.I asked Bill"what time did you go to bed last night"

-->I asked Bill.. ............ ... ....... . ............ . .... ...... ... . ....................

7.Paul said"I must go home now"

-->Paul said that........... .. ........... . . . ........

8."We are waiting for the school bus"said the children

-->The children said that............ .. .... .. ..... . .... ...... . .............

9."Must you go now"said Mr Brown

-->Mr Brown asked me...... .......... ................... ....

10."Are you going to visit your aunt tomorrow? "Asked Tom

-->Tom asked....... .... ... . . ................. ... ........ .. .. ............ ..... ..

11."Listen to me and don't make a noise"said the teacher to his students

-->The teacher asked his students................ ......... ..... .. ... . ........... .......... ..... ........

12."The sun always rices in the east"said Peter

-->Peter said............... ...... .... .............................

13."you must do your homework evryday"said Miss Lan to us

-->Miss Lan told us.......... ............................................. .............................

IV. Hoàn thành các câu hỏi sau

1.Hoa won't be late,......... ............ ........ ?

2.You're hungry.. ................... ..?

3.Lan doesn't know the answer,... ......... ..?

4.He can speak English,.. ....... . ............ .... ..?

5.You uncle is a journalist,.. ..... ..... .... .......?

6.She hasn't sent any e-mail to her friends,.. . ................... .......?

7.Your parents worked in a factory, ... ....... ............. .......?

8.She will be here tomorrow,.. . ..... ..... ............ ?

9.This picture is yours,..... ...... ...........?

10.Let's go somewhere for a drink,................... ... ...?