(1-1/2)×(1-1/3)×(1-1/4 )×...×(1-1/2006)×(1-1/2007)
=(2/2-1/2)×(3/3-1/3)×(4/4-1/4)×..×(2006/2006-1/2006)×(2007/2007-1/2007)
=1/2×2/3×3/4×..×2005/2006×2006/2007
=1/2007
Tính nhanh bài toán sau
\(\left(\frac{19}{20}x\frac{3}{4}+\frac{1}{20}x\frac{3}{4}\right)x\left(\frac{1}{2}x\frac{3}{4}-\frac{2}{4}x\frac{3}{4}\right)\)
Tính nhanh :
\(\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{3}\right)x\left(1-\frac{1}{4}\right)x....x\left(1-\frac{1}{50}\right)\)
a)Tính bằng cách thuận tiện nhất :
\(\frac{1}{2}x\frac{1}{3}+\frac{1}{3}x\frac{1}{4}+\frac{1}{4}x\frac{1}{5}+\frac{1}{5}x\frac{1}{6}\)
b) Tính :
\(\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{3}\right)x\left(1-\frac{1}{4}\right)\)
( 2006 x 2005 + 2005 + 2004 ) x (1 + \(\frac{1}{2}:\frac{3}{2}-\frac{3}{4}\)) = ?
Tính bằng cáh thuân tiện nhất
1- (\(1-\left(\frac{1}{2}x\frac{3}{5}+\frac{1}{5}x\frac{1}{2}+\frac{2}{10}x\frac{1}{2}+\frac{1}{2}\right)\)
tính nhanh
\(\frac{4}{9}x\frac{3}{7}+\frac{5}{7}x\frac{4}{9}-\frac{4}{9}x\frac{1}{7}\)
(\(1-\frac{1}{3}\)) x (\(1-\frac{1}{4}\)) x (\(1-\frac{1}{5}\)) x (\(1-\frac{1}{6}\)) x (\(1-\frac{1}{7}\)) x (\(1-\frac{1}{8}\)) \(-\frac{1}{4}\)\(x\frac{1}{2}\)
\(x\)là nhân nhé
lm hộ pls
\(\frac{1}{2}x\frac{1}{3}x\frac{1}{4}x\frac{1}{5}\)
Tính nhanh: 1,
\(\frac{423134x846267-423133}{846267x423133+423134}\)
2, 1919 x 18 - 1818 x 19
3, \(\frac{272727x28-282828x27}{1+2+3+.......+2014}\)
4, \(\frac{2929-101}{2x1919+404}\)
5, \(\frac{2}{7}-\frac{3}{8}+\frac{11}{7}+\frac{1}{3}+\frac{1}{7}-\frac{5}{8}\)
