Đặt 

\(A=210.\left(\frac{111111}{121212}+\frac{111111}{202020}+\frac{111111}{303030}+\frac{111111}{424242}+\frac{111111}{565656}+\frac{111111}{727272}+\frac{111111}{909090}\right)\)

     \(=210.\left(\frac{11}{12}+\frac{11}{20}+\frac{11}{30}+\frac{11}{42}+\frac{11}{56}+\frac{11}{72}+\frac{11}{90}\right)\)

    \(=210.11\left(\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}+\frac{1}{56}+\frac{1}{72}+\frac{1}{90}\right)\)

     \(=2310.\left(\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}+\frac{1}{7.8}+\frac{1}{8.9}+\frac{1}{9.10}\right)\)

    \(=2310.\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+\frac{1}{6}-\frac{1}{7}+\frac{1}{7}-\frac{1}{8}+\frac{1}{8}-\frac{1}{9}+\frac{1}{9}-\frac{1}{10}\right)\)

     \(=2310.\left(\frac{1}{3}-\frac{1}{10}\right)\)

       \(=2310.\frac{7}{30}\)

        \(=539\)

210.(111111/121212 +111111/202020+11111/303030 + 111111/424242 +111111/565656 +111111/727272 +111111/909090)

= 210 . ( 11/12+11/20+11/42+11/56+11/72+11/90)

= 210.(11.(1/12+1/20+1/42+1/56+1/72+1/90))

=210.(11(1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10))

=210.(11.(1/3-1/10))

=210.(11.7/30)

=210.77/30

=593

 T I C K    GIÙM MIK

8+8+8+88+888=1000

8 + 8 + 8 + 88 + 888 = 1000

8  +   8    +    8     +       88     +        888        =        1000

\(8+8+8+88+888=1000\)

\(8+8+88+888=1000\)

1000

1000              (  K  MIK  NHA  )

k mình trc

                                  \(\text{Giải:}\)

\(\text{ƯCLN(9999999, 88888888)}\)

\(\text{Ta có : 9999999 = 32 . 1111111, 8888888 = 23 . 1111111}\)

\(=>ƯCLN\left(9999999,8888888\right)=1111111\)

\(\text{Vậy ƯCLN(9999999, 8888888) = 1111111}\)

\(A=\frac{111111}{121212}+\frac{111111}{202020}+\frac{111111}{303030}\)

\(A=\frac{11}{12}+\frac{11}{20}+\frac{11}{30}\)

\(A=\frac{55}{60}+\frac{33}{60}+\frac{22}{60}\)

\(A=\frac{110}{60}=\frac{11}{6}\)

tại sao bạn nhấn lớp 0

0

k tui nha

Kết quả là 0

Câu trả lời là 0

K mk nha, mk nhanh nè

Chúc giỏi nha

111111-111111=0

111111-111111=0

k mk nha

ai k mk mk k lại

=0 nha.

ai k mik mik k lại ok

1111111+111111+111111₫13333333

1111111+111111+111111

=1111111+111111.2

=1111111+222222

=1333333

1111111+1111111+1111111

= 1111111x3

=3333333