BT1: Tính
5) ( 2008 - \(\frac{2}{135}\) + \(\frac{1}{50}\) ) - ( 1 - \(\frac{7}{135}\) + \(\frac{4}{150}\)) - ( 5 + \(\frac{5}{135}\) + \(\frac{3}{50}\))
\(\left(2018-\frac{2}{135}+\frac{1}{50}\right)-\left(1-\frac{7}{135}+\frac{4}{50}\right)-\left(5+\frac{5}{135}+\frac{3}{50}\right)\)
\(\left(2018-\frac{2}{135}+\frac{1}{50}\right)-\left(1-\frac{7}{135}+\frac{4}{50}\right)-\left(5+\frac{5}{135}+\frac{3}{50}\right)\)
\(=2018-\frac{2}{135}+\frac{1}{50}-1+\frac{7}{135}-\frac{4}{50}-5-\frac{5}{135}-\frac{3}{50}\)
\(=2012-\frac{6}{50}\)
( 2018 - \(\frac{2}{135}\)+ \(\frac{1}{50}\)) - ( 1 - \(\frac{7}{135}\)+ \(\frac{4}{50}\)) - (5 + \(\frac{5}{135}\)+ \(\frac{3}{50}\))
Tính nhanh phân số \(A=\frac{7}{5}+\frac{7}{15}+\frac{7}{45}+\frac{7}{135}+\frac{7}{405}+\frac{7}{1215}\)
a) \(\frac{-1}{3}-\frac{8}{35}+\frac{-2}{9}-\frac{1}{135}+\frac{4}{5}+\frac{-4}{9}+\frac{3}{7}\)
b) \(\frac{0,75+0,6-\frac{3}{7}-\frac{3}{13}}{2,75+2,2-\frac{11}{7}-\frac{11}{13}}\)
1. tìm x
2x -3 = x + 1/2
2. tính bằng hai cách
A = ( 2008 - 2/135 +1/50) - ( 1 - 7/135 +4/50) - ( 5+ 5/135 +3/50)
cần gấp nha
Mk giải câu 1 nha
1) 2x - 3 = x + 1/2
➡️2x - x = 1/2 + 3
➡️x = 7/2
Hok tốt~
Chứng minh rằng\(\frac{1}{1!}+\frac{1}{2!}+\frac{1}{3!}+..+\frac{1}{2015!}
Đặt A = \(\frac{1}{1!}+\frac{1}{2!}+\frac{1}{3!}+...+\frac{1}{2015!}\)
A < \(1+\frac{1}{1.2}+\frac{1}{2.3}+....+\frac{1}{2014.2015}\)
A < \(1+1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+....+\frac{1}{2014}-\frac{1}{2015}\)
A < \(2-\frac{1}{2015}\)< 2 < \(2\left(\frac{135^2+136}{136^2-135}\right)\)
=> A < \(2\left(\frac{135^2+136}{136^2-135}\right)\)(Đpcm)
tính bằng cách thuận tiện nhất
( 2008 - 2/135 + 1/50) - (1 - 7/135 + 4/50) - (5 + 5/135 + 3/50)
\(=2008-\dfrac{2}{135}+\dfrac{1}{50}-1+\dfrac{7}{135}-\dfrac{4}{50}-5-\dfrac{5}{135}-\dfrac{3}{50}\)
\(=2002\)
a.\(\left(3-\frac{3}{4}+\frac{2}{3}\right)-\left(2+\frac{4}{3}-\frac{3}{2}\right)-\left(1-\frac{7}{3}-\frac{9}{2}\right)\)
b.\(-\frac{1}{3}-\frac{8}{35}+-\frac{2}{9}-\frac{1}{135}+\frac{4}{5}+\frac{4}{-9}+\frac{3}{7}\)
Tính nhanh
a. B=5/6 -6/7+7/8-8/9+9/10-5/6+6/7+7/8+8/9
b. (2008-2/135+1/50) - (1-7/135+4/50) _ ( 5 + 5/135+3/50)
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