Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bài làm:
Ta có:
\(B=-66\cdot\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{11}\right)+124.\left(-37\right)+63.\left(-124\right)\)
\(B=\left(-66\right).\frac{1}{2}+66.\frac{1}{3}-66.\frac{1}{11}-124.\left(37+63\right)\)
\(B=-33+22-6-124.100\)
\(B=17-12400\)
\(B=-12383\)
\(B=-66.\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{11}\right)+124.\left(-37\right)+63.\left(-124\right)\)
\(=-66.\frac{1}{2}-\left(-66\right).\frac{1}{3}+\left(-66\right).\frac{1}{11}+\left(-124\right).37+63.\left(-124\right)\)
\(=-33+22-6+\left(-124\right).\left(37+63\right)\)
\(=-11-6+\left(-124\right).100\)
\(=-17-12400\)
\(=-12417\)
\(\frac{423134.846267-423133}{423133.846267+423134}=\frac{423133.846267+846247-423133}{423133.846267+423134}\)
\(=\frac{423133.846267+423134}{423133.846267+423134}=1\)
A=1/3*7+1/7*11+..+1/95*99
=> 4A=4/3*7+4/7*11+..+4/95*99
=>4A=1/3-1/7+1/7-1/11+...+1/95-1/99=1/3-1/99=32/99
=>A=8/99
\(=\frac{1}{4}\left(\frac{4}{3.7}+\frac{4}{7.11}+\frac{4}{11.15}+.......+\frac{4}{95.99}\right)=\frac{1}{4}\left(\frac{1}{3}-\frac{1}{99}\right)\)
\(=\frac{1}{4}.\frac{32}{99}=\frac{8}{99}\)
\(\frac{3}{5}-\frac{7}{45}+\frac{11}{9.13}-\frac{15}{13.17}+\frac{19}{17.21}-\frac{23}{21.25}\)
\(=\frac{3}{5}-\frac{7}{45}+\frac{11}{117}-\frac{15}{221}+\frac{19}{357}-\frac{23}{42}\)
\(=\left(\frac{-7}{45}-\frac{15}{221}-\frac{23}{42}\right)+\left(\frac{3}{5}+\frac{11}{117}+\frac{19}{357}\right)\)
đến đây bạn tự tính nhé.