Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(5\frac{3}{7}+\frac{7}{29}-0,7-\frac{3}{17}+\frac{22}{19}-2,3\)
\(=\frac{38}{7}+\frac{7}{29}-\frac{7}{10}-\frac{3}{17}+\frac{22}{19}-\frac{23}{10}\)
\(=\left(-\frac{7}{10}-\frac{23}{10}\right)+\frac{38}{7}+\frac{7}{29}-\frac{3}{17}+\frac{22}{19}\)
\(=\left(-3\right)+\frac{38}{7}+\frac{7}{29}-\frac{3}{17}+\frac{22}{19}\)
\(=\frac{17}{7}+\frac{7}{29}-\frac{3}{17}+\frac{22}{19}\)
\(=\frac{8605}{3451}+\frac{22}{19}\)
\(\approx4.\)
d) \(\sqrt{0,36}-\sqrt{0,81}+\sqrt{0,49}\)
\(=0,6-0,9+0,7\)
\(=\left(-0,3\right)+0,7\)
\(=0,4.\)
Chúc bạn học tốt!
a) \(\frac{-2}{5}+\frac{3}{10}+\frac{-3}{5}\)
\(=\left[\left(-\frac{2}{5}\right)+\left(-\frac{3}{5}\right)\right]+\frac{3}{10}\)
\(=\left(-1\right)+\frac{3}{10}\)
\(=-\frac{7}{10}.\)
c) \(15\frac{1}{4}:\frac{5}{7}-25\frac{1}{4}:\frac{5}{7}\)
\(=\frac{61}{4}:\frac{5}{7}-\frac{101}{4}:\frac{5}{7}\)
\(=\left(\frac{61}{4}-\frac{101}{4}\right):\frac{5}{7}\)
\(=\left(-10\right):\frac{5}{7}\)
\(=-14.\)
Chúc bạn học tốt!
B = \(\frac{1}{1.3}+\frac{1}{3.5}+...+\frac{1}{2015.2017}\)
B = \(\frac{1}{2}\left(\frac{1}{1}-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+...+\frac{1}{2015}-\frac{1}{2017}\right)\)
B = \(\frac{1}{2}\left(\frac{1}{1}-\frac{1}{2017}\right)\)
B = \(\frac{1}{2}\left(\frac{2017}{2017}-\frac{1}{2017}\right)\)
B = \(\frac{1}{2}.\frac{2016}{2017}\)
B = \(\frac{1008}{2017}\)
Vậy B = \(\frac{1008}{2017}\)
Chúc bạn học tốt . Có bài gì khó mik sẽ giúp bạn ( Chỉ toán 6 hoặc 7 trở xuống thui đó )
\(B=\frac{1}{1\cdot3}+\frac{1}{3\cdot5}+...+\frac{1}{2015\cdot2017}\)
\(B=\frac{1}{2}\left(\frac{2}{1\cdot3}+\frac{2}{3\cdot5}+...+\frac{2}{2015\cdot2017}\right)\)
\(B=\frac{1}{2}\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+...+\frac{1}{2015}-\frac{1}{2017}\right)\)
\(B=\frac{1}{2}\left(1-\frac{1}{2017}\right)\)
\(B=\frac{1}{2}\cdot\frac{2016}{2017}\)
\(B=\frac{1008}{2017}\)
a) \(\frac{17}{9}-\frac{17}{9}:\left(\frac{7}{3}+\frac{1}{2}\right)\)
= \(\frac{17}{9}-\frac{17}{9}:\frac{17}{6}\)
= \(\frac{17}{9}-\frac{2}{3}\)
= \(\frac{11}{9}\)
b) \(\frac{4}{3}.\frac{2}{5}-\frac{3}{4}.\frac{2}{5}\)
= \(\frac{2}{5}.\left(\frac{4}{3}-\frac{3}{4}\right)\)
= \(\frac{2}{5}.\frac{7}{12}\)
= \(\frac{7}{30}\)
Mình lười làm quá, hay mình nói kết quả cho bn thôi nha
c) -6
d) 3
e) 3
g) 12
h) \(\frac{23}{18}\)
i) \(\frac{-69}{20}\)
k) \(\frac{-1}{2}\)
l) \(\frac{49}{5}\)
a,(1/3/7-2/1/4) . 3/1/3
= -23/28 .3/1/3
= -115/42
b,(2/1/3+3/1/2):(-4/1/6+3/1/7)+7/1/2
= 35/6 : -43/42 +7/1/2
= -245/43 +7/1/2
= 155/86
\(\left(1\frac{3}{7}-2\frac{1}{4}\right).3\frac{1}{3}\)
\(=\left(\frac{10}{7}-\frac{9}{4}\right).\frac{10}{3}\)
\(=-\frac{23}{28}.\frac{10}{3}\)
\(=\frac{-115}{42}\)