Đại số lớp 7
Các câu hỏi tương tự
\(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}+\dfrac{x+1}{13}=\dfrac{x+1}{14}+\dfrac{x+1}{15}\)
\(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\)
\(\dfrac{1}{3}-\dfrac{3}{4}-\left(-\dfrac{3}{5}\right)+\dfrac{1}{64}-\dfrac{2}{9}-\dfrac{1}{36}+\dfrac{1}{15}\)
Mn giúp mk làm bài này nhoa !!!
Bài 1:1/left(-dfrac{25}{13}right)+left(-dfrac{19}{17}right)+dfrac{12}{13}+left(-dfrac{25}{17}right) 6/ 2dfrac{2}{15}.dfrac{9}{17}.dfrac{3}{32}:left(-dfrac{3}{17}right)2/dfrac{1}{2}-left(-dfrac{1}{3}right)+dfrac{1}{23}+dfrac{1}{6} 7/left(dfrac{-3}{4}+dfrac{2}{5}right):dfrac{3}{7}+left(dfrac{3}{5}+dfrac{-1}{4}right):dfrac{3}{7}3/left(-dfrac{3}{7}right).dfrac{5}{11}+left(-dfrac{5}{14}right).dfrac{5}{11} ...
Đọc tiếp
Bài 1:
1/\(\left(-\dfrac{25}{13}\right)+\left(-\dfrac{19}{17}\right)+\dfrac{12}{13}+\left(-\dfrac{25}{17}\right)\) 6/ \(2\dfrac{2}{15}.\dfrac{9}{17}.\dfrac{3}{32}:\left(-\dfrac{3}{17}\right)\)
2/\(\dfrac{1}{2}-\left(-\dfrac{1}{3}\right)+\dfrac{1}{23}+\dfrac{1}{6}\) 7/\(\left(\dfrac{-3}{4}+\dfrac{2}{5}\right):\dfrac{3}{7}+\left(\dfrac{3}{5}+\dfrac{-1}{4}\right):\dfrac{3}{7}\)
3/\(\left(-\dfrac{3}{7}\right).\dfrac{5}{11}+\left(-\dfrac{5}{14}\right).\dfrac{5}{11}\) 8/\(\left(-\dfrac{1}{3}\right).\left(-\dfrac{15}{19}\right).\dfrac{38}{45}\)
4/\(\left(-\dfrac{5}{11}\right).\dfrac{7}{15}.\dfrac{11}{-5}.\left(-30\right)\) 9/\(\dfrac{1}{2.3}+\dfrac{1}{3.4}+\dfrac{1}{4.5}+......+\dfrac{1}{19.20}\)
5/\(\left(-\dfrac{5}{9}\right).\dfrac{3}{11}+\left(-\dfrac{13}{18}\right).\dfrac{3}{11}\) 10/\(\dfrac{1}{9.10}-\dfrac{1}{8.9}-\dfrac{1}{7.8}-......-\dfrac{1}{2.3}-\dfrac{1}{1.2}\)
Tính nhanh:
a, \(\dfrac{8}{9}-\dfrac{1}{72}-\dfrac{1}{56}-\dfrac{1}{42}-\dfrac{1}{30}-\dfrac{1}{20}-\dfrac{1}{12}-\dfrac{1}{6}-\dfrac{1}{2}\)
b, \(\left(-\dfrac{1}{4}+\dfrac{7}{35}-\dfrac{5}{3}\right)-\left(-\dfrac{15}{12}+\dfrac{6}{11}-\dfrac{48}{49}\right)\)
Bài 1: tính M :N biết:
a) Ndfrac{1}{2}+dfrac{1}{3}+dfrac{1}{4}+.......+dfrac{1}{2007}+dfrac{1}{2008} và M dfrac{2007}{1}+dfrac{2006}{2}+dfrac{2005}{3}+.......+dfrac{2}{2006}+dfrac{1}{2007}
b) M dfrac{1}{11.13}+dfrac{1}{13.15}+dfrac{1}{15.17}+.......+dfrac{1}{31.33}+dfrac{1}{33.35} và N dfrac{12}{11.13.15}+dfrac{12}{13.15.17}+dfrac{12}{15.17.19}+.....+dfrac{12}{31.33.35}
Đọc tiếp
Bài 1: tính M :N biết:
a) N=\(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+.......+\dfrac{1}{2007}+\dfrac{1}{2008}\) và M= \(\dfrac{2007}{1}+\dfrac{2006}{2}+\dfrac{2005}{3}+.......+\dfrac{2}{2006}+\dfrac{1}{2007}\)
b) M= \(\dfrac{1}{11.13}+\dfrac{1}{13.15}+\dfrac{1}{15.17}+.......+\dfrac{1}{31.33}+\dfrac{1}{33.35}\) và N= \(\dfrac{12}{11.13.15}+\dfrac{12}{13.15.17}+\dfrac{12}{15.17.19}+.....+\dfrac{12}{31.33.35}\)
So sánh
a, \(\dfrac{2005^{2014}+1}{2005^{2015}+1}\&\dfrac{2005^{2016}+1}{2005^{2017}+1}\)
b, \(\dfrac{19}{10}\&\dfrac{49}{40}\)
c, \(\dfrac{13}{20}\&\dfrac{33}{40}\)
Tìm số hữu tỉ x, biết rằng:
a. \(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\)
b. \(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)
Tìm x:
a) \(\dfrac{\left(x+1\right)}{10}+\dfrac{\left(x+1\right)}{11}+\dfrac{\left(x+1\right)}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\)
b) \(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)
a) dfrac{1}{3}-dfrac{3}{5}+dfrac{5}{7}-dfrac{7}{9}+dfrac{9}{11}-dfrac{11}{13}+dfrac{13}{15}+dfrac{11}{13}-dfrac{9}{11}+dfrac{7}{9}-dfrac{5}{7}+dfrac{3}{5}-dfrac{1}{3}
b)dfrac{1}{99}-dfrac{1}{99.98}-dfrac{1}{98.97}-dfrac{1}{97.96}-.....-dfrac{1}{3.2}-dfrac{1}{2.1}
c) dfrac{1}{1.3}+dfrac{1}{3.5}+.....+dfrac{1}{left(2n-1right)left(2n+1right)}+......+dfrac{1}{255.257}
Đọc tiếp
a) \(\dfrac{1}{3}-\dfrac{3}{5}+\dfrac{5}{7}-\dfrac{7}{9}+\dfrac{9}{11}-\dfrac{11}{13}+\dfrac{13}{15}+\dfrac{11}{13}-\dfrac{9}{11}+\dfrac{7}{9}\)\(-\dfrac{5}{7}+\dfrac{3}{5}-\dfrac{1}{3}\)
b)\(\dfrac{1}{99}-\dfrac{1}{99.98}-\dfrac{1}{98.97}-\dfrac{1}{97.96}-.....-\dfrac{1}{3.2}-\dfrac{1}{2.1}\)
c) \(\dfrac{1}{1.3}+\dfrac{1}{3.5}+.....+\dfrac{1}{\left(2n-1\right)\left(2n+1\right)}+......+\dfrac{1}{255.257}\)
Tìm x
a)\(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\)
b)\(\dfrac{x+4}{2014}+\dfrac{x+3}{2015}=\dfrac{x+2}{2016}+\dfrac{x+1}{2017}\)
CẢM ƠN CÁC BẠN NHÌU ^_^