2-5/3+7/6-9/10+11/15-13/21+15/28-17/36+19/45-21/55+23/66

A=13/25 + 9/10 - 11/15 + 13/21 - 15/28 + 17/36 - a/b +  ..... + 197/4851 - 199/4950

a) a/b là phân số nào

b) Chứng minh A>9/10

cả 2 câu đều ghi cách giải ra hộ mik nha bạn nào lm đầu mik sẽ tick

cho A=1,01+1,02+1,03+...+9,98+9,99+10

B=2-5/3+7/6-9/10+11/15-13/21+15/28-17/36+19/45

      tinh 2A+455/3(B)

C= 2-\(\dfrac{5}{3}\)+\(\dfrac{7}{6}\)-\(\dfrac{9}{10}\)+\(\dfrac{11}{15}\)-\(\dfrac{13}{21}\)+\(\dfrac{15}{28}\)-\(\dfrac{17}{36}\)+\(\dfrac{19}{45}\)

tính C

Cho A= 13/25+9/10-11/15+13/21-15/28+17/36-...+197/4851-199/4950

Chứng minh A>9/10.

Giải giúp mik với, mik đang cần gấp.

Cảm ơn mọi người nhìu nhé!!!

Tìm x, biết:

\(x=\left(2-\frac{5}{3}+\frac{7}{6}-\frac{9}{10}+\frac{11}{15}-\frac{13}{21}+\frac{15}{28}-\frac{17}{36}+\frac{19}{45}\right)\times\frac{5}{3}\)

38/25+9/10-11/15+13/21-15/28+17/36-19/45+21/55=

4.24.5^2-(3^3.18+3^3.12)

31.15.7^2.4-31.49.40

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

1+3+5+7+9+11+13+15+19

2+6+10+14+22+23+26+34

5+8+11+14+17+20+23+26+29

1+6+11+16+21+26+31+36+41+47+51

10+13+16+19+22+25+28+31+34+37+40

5+7+9+11+13+15+17+3+8+13+18+23+28

4+7+10+13+16+19+5+9+13+17+21+25

Cho A = 1,01 + 1,02 + 1,03 +...+ 9,98 + 9,99 + 10

\(B=2-\frac{5}{3}+\frac{7}{6}-\frac{9}{10}+\frac{11}{15}-\frac{13}{21}+\frac{15}{28}-\frac{17}{36}+\frac{19}{45}\)

Tính 2A - 6508B