Violympic toán 6
Các câu hỏi tương tự
Tìm x,y biết \(\dfrac{1-2y}{18}=\dfrac{1+4y}{24}=\dfrac{1+6y}{6x}\)
Tìm x,y,z biết \(\dfrac{x}{3}=\dfrac{y}{4}\) ; \(\dfrac{y}{5}=\dfrac{z}{7}\) và x+y+z =9^2
Tìm n để A= 12n^2 - 5n -25 là số nguyên tố
ko dùng máy tính
\(\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{9}+\dfrac{1}{10}+\dfrac{1}{11}+\dfrac{1}{12}+\dfrac{1}{14}+\dfrac{1}{15}+\dfrac{1}{18}+\dfrac{1}{22}+\dfrac{1}{24}+\dfrac{1}{28}+\dfrac{1}{33}\)
tìm số nguyên x,y biết:
\(\dfrac{1}{x}-\dfrac{1}{y}=\dfrac{1}{2}\)
10 tháng 4 2021 lúc 22:28
Tìm x∈Z, biết:a) left(x-20right)+left(x-19right)+left(x-18right)+...+99+100100b) 213-x.left(dfrac{1}{2}+dfrac{1}{2^2}+dfrac{1}{2^3}+...+dfrac{1}{2^{2020}}right):left(1-dfrac{1}{2^{2020}}right)13
Đọc tiếp
\(Tìm\) \(x\)∈\(Z\)\(,\) \(biết\)\(:\)
\(a\)) \(\left(x-20\right)+\left(x-19\right)+\left(x-18\right)+...+99+100=100\)
\(b\)) \(213-x.\left(\dfrac{1}{2}+\dfrac{1}{2^2}+\dfrac{1}{2^3}+...+\dfrac{1}{2^{2020}}\right):\left(1-\dfrac{1}{2^{2020}}\right)=13\)
Ánh Lê
b) \(\dfrac{3}{y}< \dfrac{y}{7}< \dfrac{4}{y}\)
c) \(\dfrac{1}{8}< \dfrac{x}{18}< \dfrac{y}{24}< \dfrac{2}{9}\)
6 tháng 4 2021 lúc 20:57
Tìm các số nguyên x và y biết \(\dfrac{x}{7}+\dfrac{1}{y}=\dfrac{-1}{14}\) ( với y ≠ 0 )
31 tháng 3 2021 lúc 13:02
Tìm \(a,b\in Z\) biết \(\dfrac{a}{9}-\dfrac{3}{b}=\dfrac{1}{18}\)
4 tháng 2 2021 lúc 12:31
a) Tính A ( 1 - dfrac{1}{2} )( 1 - dfrac{1}{3} ) (1-dfrac{1}{4} ) ....(1-dfrac{1}{2014} ) (1-dfrac{1}{2015} ) (1-dfrac{1}{2016} )b)Tìm x biết dfrac{x-2}{12} + dfrac{x-2}{20} + dfrac{x-2}{30}+ dfrac{x-2}{42} + dfrac{x-2}{56} +dfrac{x-2}{72} dfrac{16}{9}
Đọc tiếp
a) Tính A = ( 1 - \(\dfrac{1}{2}\) )( 1 - \(\dfrac{1}{3}\) ) (1-\(\dfrac{1}{4}\) ) ....(1-\(\dfrac{1}{2014}\) ) (1-\(\dfrac{1}{2015}\) ) (1-\(\dfrac{1}{2016}\) )
b)Tìm x biết \(\dfrac{x-2}{12}\) + \(\dfrac{x-2}{20}\) + \(\dfrac{x-2}{30}\)+ \(\dfrac{x-2}{42}\) + \(\dfrac{x-2}{56}\) +\(\dfrac{x-2}{72}\) = \(\dfrac{16}{9}\)
text{Tìm x, biết:}a) x-dfrac{2}{3.5}-dfrac{2}{5.7}-dfrac{2}{7.9}-dfrac{2}{9.11}-dfrac{2}{11.13}-dfrac{2}{13.15}dfrac{2}{5}b) dfrac{1}{2.3}.x+dfrac{1}{3.4}.x+dfrac{1}{4.5}.x+...+dfrac{1}{49.50}.x1c) x-dfrac{20}{11.3}-dfrac{20}{13.15}-...-dfrac{53}{55}dfrac{3}{11}d) x+dfrac{4}{5.9}+dfrac{4}{9.13}+...+dfrac{4}{41.45}dfrac{-37}{45}e) left(dfrac{11}{12}.dfrac{11}{2.23}.dfrac{11}{23.34}...dfrac{11}{89.100}right).xdfrac{5}{3}f) left(dfrac{2}{11.13}.dfrac{2}{13.15}.dfrac{2}{15.17}...dfrac{2}{19.21}right...
Đọc tiếp
\(\text{Tìm x, biết:}\)
\(a\)) \(x-\dfrac{2}{3.5}-\dfrac{2}{5.7}-\dfrac{2}{7.9}-\dfrac{2}{9.11}-\dfrac{2}{11.13}-\dfrac{2}{13.15}=\dfrac{2}{5}\)
\(b\)) \(\dfrac{1}{2.3}.x+\dfrac{1}{3.4}.x+\dfrac{1}{4.5}.x+...+\dfrac{1}{49.50}.x=1\)
\(c\)) \(x-\dfrac{20}{11.3}-\dfrac{20}{13.15}-...-\dfrac{53}{55}=\dfrac{3}{11}\)
\(d\)) \(x+\dfrac{4}{5.9}+\dfrac{4}{9.13}+...+\dfrac{4}{41.45}=\dfrac{-37}{45}\)
\(e\)) \(\left(\dfrac{11}{12}.\dfrac{11}{2.23}.\dfrac{11}{23.34}...\dfrac{11}{89.100}\right).x=\dfrac{5}{3}\)
\(f\)) \(\left(\dfrac{2}{11.13}.\dfrac{2}{13.15}.\dfrac{2}{15.17}...\dfrac{2}{19.21}\right)-x+4+\dfrac{221}{231}=\dfrac{7}{3}\)