Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{11}{15}+\frac{23}{16}-\left(5+\frac{27}{16}-\frac{19}{15}\right)+\left(\frac{-1}{2}\right)^2\)
\(=\frac{11}{15}+\frac{23}{16}-5-\frac{27}{16}+\frac{19}{15}+\frac{1}{4}\)
\(=\left(\frac{11}{15}+\frac{19}{15}\right)+\left(\frac{23}{16}-\frac{27}{16}\right)-5+\frac{1}{4}\)
\(=\frac{30}{15}-\frac{4}{16}-5+\frac{1}{4}\)
\(=2-\frac{1}{4}-5+\frac{1}{4}\)
\(=-3\)
học tốt ngôlãmtân
\(\frac{11}{15}+\frac{23}{16}-\left(5+\frac{27}{16}-\frac{19}{15}\right)+\left(-\frac{1}{2}\right)^2\) = \(\frac{11}{15}+\frac{23}{16}-5-\frac{27}{16}+\frac{19}{15}+\frac{1}{4}\)
\(=2-\frac{1}{4}-5+\frac{1}{4}=2-5=-3\)
Kb với mình nha!
a) \(=\left(13\dfrac{2}{7}+2\dfrac{5}{7}\right):\left(-\dfrac{8}{9}\right)\)
\(=16:\dfrac{-8}{9}=\dfrac{-8\cdot\left(-2\right)\cdot9}{-8}=-18\)
b)
\(=\left(\dfrac{-6}{11}\cdot\dfrac{11}{-6}\right)\cdot\dfrac{7\cdot10\cdot\left(-2\right)}{10}\)
\(=-14\)
c) \(=\dfrac{-1}{2}\cdot\dfrac{4}{3}\cdot\dfrac{-7}{2}\)
\(=\dfrac{-1\cdot2\cdot2\cdot\left(-7\right)}{2\cdot3\cdot2}=\dfrac{7}{3}\)
\(a.\left[-\dfrac{6}{11}.\dfrac{11}{-6}\right].\dfrac{7}{10}.\left(-20\right)=1.7.\left(-2\right)=-14\)
\(b.\dfrac{-1}{2}:\dfrac{3}{4}.\dfrac{-7}{2}=\dfrac{7}{4}:\dfrac{3}{4}=\dfrac{7}{3}\)
\(c.\dfrac{93}{7}:-\dfrac{8}{9}+\dfrac{19}{7}:\dfrac{-8}{9}=\left(\dfrac{93}{7}+\dfrac{19}{7}\right):-\dfrac{8}{9}=\dfrac{-9}{8}.\dfrac{112}{7}=-18\)
\(\left(\frac{1}{4}-x\right)\left(x+\frac{2}{5}\right)=0\)
Ta xét 2 trường hợp
\(\begin{cases}\frac{1}{4}-x=0\\x+\frac{2}{5}=0\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{1}{4}\\x=-\frac{2}{5}\end{cases}}\)
tớ mới làm bài 1 thôi bài 2 3 tớ ko có thời gian
a) Ta có: \(\frac{0,4-\frac{2}{7}+\frac{2}{11}}{0,6-\frac{3}{7}+\frac{3}{11}}\)
\(=\frac{2.\left(0.2-\frac{1}{7}+\frac{1}{11}\right)}{3.\left(0,2-\frac{1}{7}+\frac{1}{11}\right)}\)
\(=\frac{2}{3}\)
b) Ta có: \(\frac{0,75-0,6+\frac{3}{7}+\frac{3}{13}}{2,75-2,2+\frac{11}{7}+\frac{11}{13}}\)
\(=\frac{3.\left(0,25-0,2+\frac{1}{7}+\frac{1}{13}\right)}{11.\left(0,25-0,2+\frac{1}{7}+\frac{1}{13}\right)}\)
\(=\frac{3}{11}\)
Chuk pạn hok tốt!
a) \(\frac{0,4-\frac{2}{7}+\frac{2}{11}}{0,6-\frac{3}{7}+\frac{3}{11}}\\ =\frac{\frac{2}{5}-\frac{2}{7}+\frac{2}{11}}{\frac{3}{5}-\frac{3}{7}+\frac{3}{11}}\\ =\frac{2\left(\frac{1}{5}-\frac{1}{7}+\frac{1}{11}\right)}{3\left(\frac{1}{5}-\frac{1}{7}+\frac{1}{11}\right)}\\=\frac{2}{3}\)
b) \(\frac{0,75-0,6+\frac{3}{7}+\frac{3}{13}}{2,75-2,2+\frac{11}{7}+\frac{11}{13}}\\=\frac{\frac{3}{4}-\frac{3}{5}+\frac{3}{7}+\frac{3}{13}}{\frac{11}{4}-\frac{11}{5}+\frac{11}{7}+\frac{11}{13}}\\=\frac{3\left(\frac{1}{4}-\frac{1}{5}+\frac{1}{7}+\frac{1}{13}\right)}{11\left(\frac{1}{4}-\frac{1}{5}+\frac{1}{7}+\frac{1}{13}\right)}\\=\frac{3}{11}\)
a: \(=\dfrac{7}{2}\left(-\dfrac{3}{4}+\dfrac{5}{13}-\dfrac{9}{4}-\dfrac{8}{13}\right)=\dfrac{7}{2}\cdot\left(-3-\dfrac{3}{13}\right)=\dfrac{7}{2}\cdot\dfrac{-42}{13}=\dfrac{-147}{13}\)
b: \(=-12+\dfrac{8}{9}-\dfrac{5}{18}=\dfrac{-216}{18}+\dfrac{16}{18}-\dfrac{5}{18}=\dfrac{-205}{18}\)
c: \(=\dfrac{45}{4}-\dfrac{19}{7}-\dfrac{21}{4}=6-\dfrac{19}{7}=\dfrac{23}{7}\)
d: \(=\dfrac{-1}{4}\left(\dfrac{152}{11}+\dfrac{68}{11}\right)=\dfrac{-1}{4}\cdot20=-5\)
\(a.=\frac{3}{15}+\frac{-10}{15}\)
\(=-\frac{7}{15}\)
\(b.=\left(\frac{15}{12}-\frac{3}{12}\right)+\left(\frac{5}{13}-\frac{18}{13}\right)\)
\(=1+\left(-1\right)\)
\(=0\)
\(c.=\left(\frac{13}{25}-\frac{38}{25}\right)+\left(\frac{6}{41}+\frac{35}{41}\right)-\frac{1}{2}\)
\(=-1+1-\frac{1}{2}\)
\(=0-\frac{1}{2}\)
\(=-\frac{1}{2}\)
\(d.=\frac{5}{6}.\left(18\frac{2}{3}-6\frac{2}{3}\right)\)
\(=\frac{5}{6}.12\)
\(=10\)
Ta thực hiện − 24 11 + 2 11 + − 19 13 + − 20 13 = ( − 2 ) + ( − 3 ) = − 5