\(=\left(12+\dfrac{3}{5}\right)\cdot\dfrac{-7}{5}+\left(2+\dfrac{2}{5}\right)\cdot\dfrac{-7}{5}\)
=-7/5(12+3/5+2+2/5)
=-15*7/5=-21
`= (12 3/5 + 2 2/5) : -5/7`
`= 15 : -5/7`
`= -21`
a)\(\dfrac{-12}{15}+\dfrac{-4}{26}\) b)\(5\dfrac{1}{3}-2\dfrac{4}{5}\)
c)\(\dfrac{4}{5}-\left(-\dfrac{2}{7}\right)+-\dfrac{5}{10}\) d)\(-1\dfrac{2}{7}+\dfrac{3}{14}-\dfrac{5}{21}\)
e)\(12-\dfrac{11}{121}+\left(-\dfrac{8}{9}\right)-\left(-\dfrac{3}{7}\right)\) f) \(\dfrac{11}{12}-\left(1\dfrac{3}{4}\right)-\dfrac{2}{16}\)
B= 0,25 +3/5 - (1/8-2/5+\(1\dfrac{1}{4}\) )
C=\(\dfrac{2}{3}-\left(\dfrac{-1}{4}\right)+\dfrac{3}{5}-\dfrac{7}{45}-\left(\dfrac{-5}{9}\right)+\dfrac{1}{12}+\dfrac{1}{35}\)
D=\(\left(5-\dfrac{3}{4}+\dfrac{1}{5}\right)-\left(6+\dfrac{7}{4}-\dfrac{8}{5}\right)-\left(2-\dfrac{5}{7}+\dfrac{16}{5}\right)\)
e) \(\dfrac{3}{3x}-\dfrac{3}{12}=\dfrac{4}{5}-\left(\dfrac{7}{x}-2\right)\)
f) \(\dfrac{1}{x-1}+\dfrac{-2}{3}\left(\dfrac{3}{4}-\dfrac{6}{5}\right)=\dfrac{5}{2-2x}\)
g) \(3-\dfrac{2}{2x-3}=\dfrac{2}{5}=\dfrac{2}{9-6x}-\dfrac{3}{2}\)
h) \(\dfrac{x}{2}-\dfrac{1}{x}=\dfrac{1}{12}\)
i) \(x^2-\dfrac{7}{6}x+\dfrac{1}{3}=0\)
k) \(\dfrac{13}{x-1}+\dfrac{5}{2x-2}-\dfrac{6}{3x-3}\)
m) \(\left(\dfrac{3}{2}-\dfrac{2}{-5}\right):x-\dfrac{1}{2}=\dfrac{3}{2}\)
n) \(\left(\dfrac{3}{2}-\dfrac{5}{11}-\dfrac{3}{13}\right)\left(2x-2\right)=\left(-\dfrac{3}{4}+\dfrac{5}{22}+\dfrac{3}{26}\right)\)
c )\(\dfrac{x}{2}-\left(\dfrac{3x}{5}-\dfrac{13}{5}\right)=-\left(\dfrac{7}{5}+\dfrac{7}{10}.x\right)\)
d)\(\dfrac{2x-3}{3}+\dfrac{-3}{2}=\dfrac{5-3x}{6}-\dfrac{1}{3}\)
Tinh:
\(\dfrac{7}{8}.\left(\dfrac{2}{12}+\dfrac{4}{10}\right)\)
\(\dfrac{3}{2}-\dfrac{5}{6}:\left(\dfrac{1}{2}\right)^2+\sqrt{4}\)
\(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{19}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
\(\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(16\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)+28\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)\)
Tính nhanh :
\(B=\dfrac{1}{5}-\dfrac{3}{7}+\dfrac{5}{9}-\dfrac{2}{11}+\dfrac{7}{13}-\dfrac{9}{16}-\dfrac{7}{13}+\dfrac{2}{11}-\dfrac{5}{9}+\dfrac{3}{7}-\dfrac{1}{5}\)
Tinh:
a) \(\dfrac{7}{8}.\left(\dfrac{2}{12}+\dfrac{4}{10}\right)\)
b) \(\dfrac{3}{2}-\dfrac{5}{6}:\left(\dfrac{1}{2}\right)^2+\sqrt{4}\)
c) \(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{19}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
d) \(\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
e) \(16\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)+28\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)\)
GIUP MK T ^ T
Bài 8:
b)\(\left(\dfrac{-4}{3}\right)+\left(\dfrac{-2}{5}\right)+\left(\dfrac{-3}{2}\right)\)
c) \(\dfrac{4}{5}-\left(\dfrac{-2}{7}\right)-\dfrac{-7}{10}\)
d) \(\dfrac{2}{3}-\left[\left(\dfrac{-7}{4}\right)-\left(\dfrac{1}{2}+\dfrac{3}{8}\right)\right]\)
