tính (0.4-2/9+2/11)/(7/9-1.4-7/11)-(1/3-0.25+1/5)/(1/1/6-0.875+0.7):(1^2+2^2+...+2018^2)
a. [0.8x(4/5x1.25)]/(0.64-1/25) + [(1.08-2/25):4/7]/[(59/9-13/4)x36/17]
b.(0.4-2/9+2/11)/(1.4-7/9+7/11) - (1/3-0.25+1/5)/(7/6-0.875+0.7)
\(B=2016:\left(\frac{0.4-\frac{2}{9}+\frac{2}{11}}{1.4-\frac{7}{9}+\frac{7}{11}}.\frac{-1\frac{1}{6}+0.875-0.7}{\frac{1}{3}-0.25+\frac{1}{5}}\right)\)
\(B=2016:\left(\frac{0.4-\frac{2}{9}+\frac{2}{11}}{1.4-\frac{7}{9}+\frac{7}{11}}.\frac{-1\frac{1}{6}+0.875-0.7}{\frac{1}{3}-0.25+\frac{1}{5}}\right)\)
<=>\(B=2016:\left(\frac{\frac{2}{5}-\frac{2}{9}+\frac{2}{11}}{\frac{7}{5}-\frac{7}{9}+\frac{7}{11}}.\frac{\frac{-7}{6}+\frac{7}{8}-\frac{7}{10}}{\frac{1}{3}-\frac{1}{4}+\frac{1}{5}}\right)\)
<=>\(B=2016:\left(\frac{2.\left(\frac{1}{5}.\frac{1}{9}.\frac{1}{11}\right)}{5.\left(\frac{1}{5}.\frac{1}{9}.\frac{1}{11}\right)}.\frac{\frac{7}{6}-\frac{7}{8}-\frac{7}{10}}{\frac{2}{6}-\frac{2}{8}-\frac{2}{10}}\right)\)
<=>\(B=2016:\left(\frac{2}{5}.\frac{7.\left(\frac{1}{6}-\frac{1}{8}-\frac{1}{10}\right)}{2.\left(\frac{1}{6}-\frac{1}{8}-\frac{1}{10}\right)}\right)\)
<=>\(B=2016:\left(\frac{2}{5}.\frac{7}{2}\right)\)
<=>\(B=2016:\frac{7}{5}\)
<=>\(B=2016.\frac{5}{7}\)
<=>\(B=1440\)
Vậy B=1440
k cho mink nha
A=\(\left(\frac{0.4-\frac{2}{9}+\frac{2}{11}}{1.4-\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-0.25+\frac{1}{5}}{1\frac{1}{6}-0.875+0.7}\right):\left(1^2+2^2+3^2+...+2015^2\right)\)
Trả lời
\(A=\left(\frac{\frac{2}{5}-\frac{2}{9}+\frac{2}{11}}{\frac{7}{5}-\frac{7}{9}+\frac{7}{11}}-\frac{2.\left(\frac{1}{6}-\frac{1}{8}-\frac{1}{10}\right)}{\frac{7}{6}-\frac{7}{8}-\frac{7}{10}}\right):\left(1^2+2^2+...+2015^2\right).\)
\(A=\left(\frac{2}{7}-\frac{2}{7}\right):\left(1^2+2^2+3^2+...+2015^2\right)\)
\(A=0:\left(1^2+2^2+3^2+.....+2015^2\right)\)
A=0
Study well
\(A=...\)
\(=\left(\frac{\frac{2}{5}-\frac{2}{9}+\frac{2}{11}}{\frac{7}{5}-\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-\frac{1}{4}+\frac{1}{5}}{\frac{7}{6}-\frac{7}{8}+\frac{7}{10}}\right):\left(1^2+2^2+...+2015^2\right)\)
\(=\left[\frac{2\left(\frac{1}{5}-\frac{1}{9}+\frac{1}{11}\right)}{7\left(\frac{1}{5}-\frac{1}{9}+\frac{1}{11}\right)}-\frac{\frac{1}{3}-\frac{1}{4}+\frac{1}{5}}{\frac{7}{2}\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{5}\right)}\right]:\left(1^2+2^2+...+2015^2\right)\)
\(=\left(\frac{2}{7}-\frac{1}{\frac{7}{2}}\right):\left(1^2+2^2+...+2015^2\right)\)
\(=\left(\frac{2}{7}-\frac{2}{7}\right):\left(1^2+2^2+...+2015^2\right)\)
\(=0:\left(1^2+2^2+...+2015^2\right)=0\)
Tính nhanh: \(B=\left(\frac{0.4-\frac{2}{9}+\frac{2}{11}}{1.4-\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-0.25+\frac{1}{5}}{1\frac{1}{6}-0.875+0.7}\right):\frac{2014}{2015}\)
A= {(0.4-2/9=2/11)/(1.4-7/9=7/11)-(1/3-0.25=1/5)/(1/1/6-0.876+0.7)};2018/2019
M.n giúp mk vs ạ..! Thanks♥♥
Bạn cần gõ lại đề bằng công thức toán thật đầy đủ (bộ gõ nằm ở biểu tượng $\sum$ ) để được hỗ trợ tốt hơn, cũng để người nhìn đỡ đau mắt. Bài này sẽ bị xóa sau khi bạn có bài post mới!
ai đó giải giúp với làm ơn nhoa
a. [0.8x(4/5x1.25)]/(0.64-1/25) + [(1.08-2/25):4/7]/[(59/9-13/4)x36/17]
b.(0.4-2/9+2/11)/(1.4-7/9+7/11) - (1/3-0.25+1/5)/(7/6-0.875+0.7)
giúp mình với nhé
Tính nhanh:
b) B=1/3+1/6+1/12+1/24+...+1/1536
c) C=0.4+2/9+2/11 - 1/3+0.25+1/5
1.4+7/9+7/11 7/6+0.875+0.7
CÁI GẠCH CHÂN CŨNG LÀ PHÂN SỐ NHA
AI NHANH NHẤT ĐÚNG NHẤT CHO 1 TICK NHA :))
\(M=\hept{\begin{cases}0.4-\frac{2}{9}+\frac{2}{11}-\frac{1}{3}-0.25+\frac{1}{5}\\1,4-\frac{7}{9}+\frac{7}{11}-1\frac{1}{6}-0.875+0.7\end{cases}}\left\{\right\}:\frac{2012}{2013}\)
cái dấu trước dấu chia mình ko biết cách đóng ngoặc nhọn lại nên mình viết như vậy
(\(\frac{0.4-\frac{2}{9}+\frac{2}{11}}{1.4-\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-0.25+\frac{1}{5}}{1\frac{1}{6}-0.875+0.7}\)):\(\frac{2014}{2015}\)
Tính giúp nhé ,cần gấp!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
làm rõ ràng ra nhé mọi người!!!!!!!!!!!!!!!!!!!!!!!!!