Violympic toán 7
Các câu hỏi tương tự
8) Adfrac{9}{10}-dfrac{1}{90}-dfrac{1}{72}-dfrac{1}{56}-dfrac{1}{42}-dfrac{1}{30}-dfrac{1}{20}-dfrac{1}{12}-dfrac{1}{6}-dfrac{1}{2}
9) Bdfrac{1}{3}+dfrac{1}{3^2}+dfrac{1}{3^4}+...+dfrac{1}{3^{2014}}+dfrac{1}{3^{2015}}
10) Pdfrac{dfrac{1}{2}+dfrac{1}{3}+dfrac{1}{4}+...+dfrac{1}{2005}}{dfrac{2004}{1}+dfrac{2003}{2}+dfrac{2002}{3}+...+dfrac{1}{2004}}
Đọc tiếp
8) \(A=\dfrac{9}{10}-\dfrac{1}{90}-\dfrac{1}{72}-\dfrac{1}{56}-\dfrac{1}{42}-\dfrac{1}{30}-\dfrac{1}{20}-\dfrac{1}{12}-\dfrac{1}{6}-\dfrac{1}{2}\)
9) \(B=\dfrac{1}{3}+\dfrac{1}{3^2}+\dfrac{1}{3^4}+...+\dfrac{1}{3^{2014}}+\dfrac{1}{3^{2015}}\)
10) \(P=\dfrac{\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+...+\dfrac{1}{2005}}{\dfrac{2004}{1}+\dfrac{2003}{2}+\dfrac{2002}{3}+...+\dfrac{1}{2004}}\)
Tìm x biết \(\dfrac{1}{3}+\dfrac{1}{6}+\dfrac{1}{10}+......+\dfrac{2}{x.\left(x+1\right)}=\dfrac{2016}{2018}\)
Tính :
A dfrac{2}{60.63}+dfrac{2}{63.66}+..........+dfrac{2}{107.120}+dfrac{2}{2006}.
B dfrac{5}{40.44}+dfrac{5}{44.48}+.....+dfrac{5}{76.80}+dfrac{5}{2006}.
C dfrac{1}{10}+dfrac{1}{40}+dfrac{1}{88}+dfrac{1}{154}+dfrac{1}{238}+dfrac{1}{340}.
D dfrac{1}{3}+dfrac{1}{6}+dfrac{1}{10}+dfrac{1}{15}+.........+dfrac{1}{2015.2018}
Đọc tiếp
Tính :
A = \(\dfrac{2}{60.63}+\dfrac{2}{63.66}+..........+\dfrac{2}{107.120}+\dfrac{2}{2006}\).
B = \(\dfrac{5}{40.44}+\dfrac{5}{44.48}+.....+\dfrac{5}{76.80}+\dfrac{5}{2006}\).
C = \(\dfrac{1}{10}+\dfrac{1}{40}+\dfrac{1}{88}+\dfrac{1}{154}+\dfrac{1}{238}+\dfrac{1}{340}\).
D = \(\dfrac{1}{3}+\dfrac{1}{6}+\dfrac{1}{10}+\dfrac{1}{15}+.........+\dfrac{1}{2015.2018}\)
tìm x biết (\(\dfrac{1}{2}\)+\(\dfrac{1}{3}\)+\(\dfrac{1}{4}\)+...+\(\dfrac{1}{2018}\)).x=\(\dfrac{2017}{1}+\dfrac{2016}{2}+\dfrac{2015}{3}+...+\dfrac{2}{2016}+\dfrac{1}{2017}\)
Tính tổng : \(1-\dfrac{1}{10}-\dfrac{1}{15}-\dfrac{1}{3}-\dfrac{1}{28}-\dfrac{1}{6}-\dfrac{1}{21}\)
Tính giá trị các biểu thức sau:
a, A = \(\left(3\dfrac{5}{6}-1\dfrac{1}{3}\right)\left(3\dfrac{4}{15}-2\dfrac{3}{5}\right)\)
b, B= \(\dfrac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\) c, C = \(\left(1-\dfrac{1}{3}\right)\left(1-\dfrac{1}{6}\right)\left(1-\dfrac{1}{10}\right)\left(1-\dfrac{1}{15}\right)...\left(1-\dfrac{1}{210}\right)\)
câu 1 . tìm x
a. \(x:3\dfrac{1}{15}=1\dfrac{1}{2}\)
b.\(x.\dfrac{3}{2}=\dfrac{-7}{6}\)
c. \(\dfrac{5}{6}+\dfrac{1}{4}:x=\dfrac{-2}{3}\)
d. \(\dfrac{-2}{13}.x=\dfrac{-9}{26}\)
e. \(\dfrac{1}{2}.x-\dfrac{1}{10}=\dfrac{2}{3}\)
f.\(-52+\dfrac{2}{3}.x=-46\)
Tìm x biết
\(\left(\dfrac{1}{2}+\dfrac{1}{3}+...+\dfrac{1}{2015}+\dfrac{1}{2016}\right)x=\dfrac{2015}{1}+\dfrac{2014}{2}+...+\dfrac{2}{2014}+\dfrac{1}{2015}\)
tính: A=\([\dfrac{1\dfrac{11}{31}.4\dfrac{3}{7}-(15-6\dfrac{1}{3}.\dfrac{2}{19})}{4\dfrac{5}{6}+\dfrac{1}{6}(12-5\dfrac{1}{3})}.(-1\dfrac{14}{93})].\dfrac{31}{50}\)