1 x 1 = 1
2 x 2 = 4
3 x 3 = 9
4 x 4 = 16
5 x 5 = 25
6 x 6 = 36
7 x 7 = 49
8 x 8 = 64
9 x 9 = 81 
10 x 10 = 100
 

\(1x1=1\)

\(2x2=4\)

\(3x3=9\)

\(4x4=16\)

\(5x5=25\)

\(6x6=36\)

\(7x7=49\)

\(8x8=64\)

\(9x9=81\)

\(10x10=100\)

1 x 1 = 1

2 x 2 = 4

3 x 3 = 9

4 x 4 = 16

5 x 5 = 25

6 x 6 = 36

7 x 7 = 49

8 x 8 = 64

9 x 9 = 81

10 x 10 = 100

1 . 1 = 1

2 . 2 = 4

3 . 3 = 9

4 . 4 = 16

5 . 5 = 25

6 . 6 = 36

7 . 7 = 49

8 . 8 = 64

9 . 9 = 81

10 . 10 = 100

11 . 11 = 121

12 . 12 = 144

13. 13 = 169

14 . 14 = 196

15 . 15 = 225

16 . 16 = 256

17 . 17 = 289

18 . 18 = 324

19 . 19 =  361

20 . 20 = 400

21. 21 = 441

22 . 22 = 484

23 . 23 = 529

24 . 24 = 576

25 . 25 = 625

26 . 26 = 676

27 . 27 = 729

28 . 28 = 784

29 . 29 = 841

30 . 30 = 900

31 . 31 = 961

32 . 32 = 1024

33 . 33 = 1089

34 . 34 = 1156

35 . 35 = 1225

36 . 36 = 1296

37 . 37 = 1369

38 . 38 = 1444

39 . 39 = 1521

40 . 40 = 1600

1 x 1 = 1

2 x 2 = 4

3 x 3 = 9

4 x 4 = 16

5 x 5 = 25

6 x 6 = 36

7 x 7 = 49

8 x 8 = 64

9 x 9 = 81

10 x 10 = 100

11 x 11 = 121

12 x 12 = 144

13 x 13 = 169

14 x 14 = 196

15 x 15 = 225

16 x 16 = 256 

17 x 17 = 289

18 x 18 = 324

19 x 19 = 361

20 x 20 = 400

21 x 21 = 441

22 x 22 = 484

23 x 23 = 529

24 x 24 = 576

25 x 25 = 625

26 x 26 = 676

27 x 27 = 729

28 x 28 = 784

29 x 29 = 841

30 x 30 = 900

31 x 31 = 961

32 x 32 = 1024

33 x 33 = 1089

34 x 34 = 1156 

35 x 35 = 1225

36 x 36 = 1296

37 x 37 = 1369

38 x 38 = 1444

39 x 39 = 1521

40 x 40 = 1600

~ Mỏi tay quá ~

1x1=1

2x2=4

3x3=9

4x4=16

5x5=25

6x6=36

7x7=49

8x8=64

9x9=81

10x10=100

11x11=121

12x12=144

13x13=169

14x14=196

15x15=225

16x16=256

17x17=289

18x18=324

19x19=361

20x20=400

21x21=441

22x22=484

23x23=529

24x24=576

25x25=625

26x26=676

27x27=729

28x28=784

29x29=841

30x30=900

31x31=961

32x32=1024

33x33=1089

34x34=1156

35x35=1225

36x36=1296

37x37=1369

38x38=1444

39x39=1521

40x40=1600

1 + 2 x 2 + 3 x 3 + 4 x 4 + 5 x 5 + 6 x 6 + 7 x 7 + 8 x 8 + 9 x 9 + 10 x 10

= 1 + 4 + 9 + 16 + 25 + 36 + 49 + 64 + 81 + 100

= 385

1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7 + 8x8 + 9x9 + 10x10

= 1+4+9+16+25+36+49+64+81+100

=(81+9)+(64+16)+(49+1)+)36+4)+25+100

=90+80+50+40+25 +100

=385

Đặt T = 1 + 2 x 2 + ... + 10 x 2 = 385

E= 2925

F= 951 

nho k cho minh nha minh dang can diem

mk cần cả bài

E= 1x1+3x3+5x5+7x7+9x9+11x11+13x13+15x15+17x17+19x19+21x21+25x25=2925

F= 4x4+7x7+10x10+13x13+16x16+19x19=951

bai nhu vay day cho minh xin mot k nha ko co cung duoc

đặt \(A=\frac{1}{2.2}+\frac{1}{3.3}+\frac{1}{4.4}+\frac{1}{5.5}+\frac{1}{6.6}+\frac{1}{7.7}+\frac{1}{8.8}=\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+\frac{1}{5^2}+\frac{1}{6^2}+\frac{1}{7^2}+\frac{1}{8^2}\)

\(A

5/8+3/5x5/12=

Ta thấy:

1/2*2<1/1*2)vì 2*2>1*2).

1/3*3<1/2*3(vì 3*3>2*3).

...

1/8*8<1/7*8(vì 8*8>7*8).

=>1/2*2+1/3*3+1/4*4+...+1/8*8<1/1*2+1/2*3+1/3*4+...+1/7*8.

=>B<1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8.

=>B<1-1/8.

=>B<7/8.

Mà 7/8<1.

=>B<1.

Vậy B<1(đpcm).

\(< \frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{4\cdot5}+\frac{1}{5\cdot6}+\frac{1}{6\cdot7}+\frac{1}{7\cdot8}\)

\(\Rightarrow1-\frac{1}{8}< 1\)

=>B<1

\(B=\frac{1}{2.2}+\frac{1}{3.3}+\frac{1}{4.4}+\frac{1}{5.5}+\frac{1}{6.6.}+\frac{1}{7.7}+\frac{1}{8.8}\)\(=\)\(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+\frac{1}{5^2}+\frac{1}{6^2}+\frac{1}{7^2}+\frac{1}{8^2}\)

\(B=\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}+\frac{1}{7.8}\)

\(B=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{7}-\frac{1}{8}\)

\(B=1-\frac{1}{8}\)

\(\Rightarrow B< 1\left(ĐPCM\right)\)

1x1=1                                 6x6=36

2x2=4                                 7x7=49

3x3=9                                 8x8=64

4x4= 16                                9x9=81

5x5=25                                 10x10=100

Tick mk vài cái cho lên 210 nha !!!

cái này lớp 2 chứ lớp 4 gì

1x1=2

2x2=4

3x3=9

4x4=16

5x5=25

6x6=36

7x7=49

8x8=64

9x9=81

10x10=100