\(A=\frac{636363.37-737373.63}{1+2...+2011}=\frac{111\left(63.\right).37-111\left(73\right).63}{\frac{2011.2012}{2}}=\frac{111.63\left(37-73\right)}{2011.1006}\)
\(A=\frac{111.63.\left(-40\right)}{2011.1006}\)
Tìm x biết:
a) \(^{2^x+2^{x+1}+2^{x+2}+2^{x+3}=480}\)
b) \(\left(\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2012}+\frac{1}{2013}\right).x=\frac{2012}{1}+\frac{2011}{2}+\frac{2010}{3}+...+\frac{2}{2011}+\frac{1}{2012}\)
1) So sánh:
A= 2010/2011 + 2011/2012 + 2012/2010
B= 1/3 + 1/4 + 1/5 + ... + 1/17
Ai nhanh mk sẽ tick
Chứng minh: A = \(\dfrac{1}{2!}+\dfrac{1}{3!}+\dfrac{1}{4!}+.....+\dfrac{1}{2011!}< 1\)
Mình đang cần giap các bn giải nhanh giùm mình nhé
\(\frac{2014\:\cdot\:18\:+\:1995\:+\:2011\:\cdot\:2013}{2013\:\cdot\:17\:+\:671\:\cdot\:3\:-\:671\:\cdot\:663}\)
Tính nhanh
a)(5\(\dfrac{1}{7}\)- 3\(\dfrac{3}{11}\)) - 2\(\dfrac{1}{7}\)-1\(\dfrac{8}{11}\)
b) (\(\dfrac{1999}{2011}-\dfrac{2011}{1999}\)) -(\(\dfrac{-12}{1999}-\dfrac{12}{2011}\))
c)(1-\(\dfrac{1}{2}\))(1-\(\dfrac{1}{3}\))............(1-\(\dfrac{1}{2017}\))
d) \(\dfrac{2}{15}.6\dfrac{5}{11}+\dfrac{5}{11}.\dfrac{-2}{15}\)\(-\dfrac{2}{15}.2015^0\)
e)\(\dfrac{1}{6}-\dfrac{1}{39}+\dfrac{1}{51}\):\(\dfrac{1}{8}-\dfrac{1}{12}+\dfrac{1}{68}\)
(1/2+1/3+..................+1/2012=1/2013).x=2012/1+2011/2+...................+2/2011+1/2012
(1/2+1/3+..................+1/2012=1/2013).x=2012/1+2011/2+...................+2/2011+1/2012
BT1: Tính nhanh:
4) (\(1-\dfrac{1}{2010}\)) . ( \(1-\dfrac{2}{2010}\)) . (\(1-\dfrac{3}{2010}\)) ...... ( \(1-\dfrac{2011}{2010}\))
so sánh: A=2^0+2^1+2^2+2^3+ ...2^2010 và B= 2^2011-1
