Rút gọn hợp lý (giải ra nhé) :
\(\dfrac{1.3.5.....39}{21.22.23...40}\)
Tính \(\dfrac{P}{A}\)biết :
P=\(\dfrac{2013}{2}+\dfrac{2013}{3}+\dfrac{2013}{4}+...+\dfrac{2013}{2014}\)
A = \(\dfrac{2013}{1}+\dfrac{2012}{2}+\dfrac{2011}{1}+....+\dfrac{1}{2013}\)
So sánh P và Q biết ;
P = \(\dfrac{2013.2014-1007.4030}{2014^2-2011.2014}\)
Q = -\(\dfrac{214263}{142842}\)
Thu gọn :
A = \(\dfrac{2}{3}+\dfrac{14}{15}+\dfrac{34}{35}+.......+\dfrac{9998}{9999}\)
Thu gọn :
A = \(\dfrac{1}{1.2}+\dfrac{2}{2.4}+\dfrac{3}{4.7}+\dfrac{4}{7.11}+\dfrac{5}{11.16}+\dfrac{6}{16.22}\)
1)Cho A=\(\dfrac{2016^{2016}+2}{2016^{2016}-1}\)và B=\(\dfrac{2016^{2016}}{2016^{2016}-3}\)
So sánh A và B
2)Tính \(\dfrac{1}{2016.2015}+\dfrac{1}{2015.2014}+\dfrac{1}{2013.2014}+..+\dfrac{1}{1.2}\)
CẢM ƠN VÌ ĐÃ GIÚP MIK NHÉ
Thu gọn :
A = \(\dfrac{7.9+14.27+21.36}{21.27+42.81+63.108}\)
So sánh
\(\dfrac{2011}{2013}+\dfrac{2013}{2015}+\dfrac{2015}{2017}+\dfrac{2017}{2011}\) và 4
tính tổng
A= \(\dfrac{1}{1.6}+\dfrac{1}{2.9}+\dfrac{1}{3.12}+...+\dfrac{1}{670.2017}\)
Thu gọn :
S = \(\dfrac{2}{3^2}+\dfrac{2}{3^4}+\dfrac{2}{3^6}+...+\dfrac{2}{3^{50}}\)