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Dấu

a) \(\left(6-\frac{2}{3}+\frac{1}{2}\right)\)- \(\left(5+\frac{5}{3}-\frac{2}{3}\right)\)- \(\left(3-\frac{7}{3}+\frac{5}{2}\right)\)

= \(6-\frac{2}{3}+\frac{1}{2}-5-\frac{5}{3}+\frac{2}{3}-3+\frac{7}{3}-\frac{5}{2}\)

= \(-2+\frac{2}{3}-\frac{4}{2}\)

= \(\frac{-12}{6}+\frac{4}{6}-\frac{12}{6}\)= \(\frac{4}{6}=\frac{2}{3}\)

a/\(\left(6-\frac{2}{3}+\frac{1}{2}\right)-\left(5+\frac{5}{3}-\frac{2}{3}\right)-\left(3-\frac{7}{3}+\frac{5}{2}\right)..\)

\(=\left(6-\frac{1}{6}\right)-\left(5+1\right)-\left(3-\frac{-1}{6}\right)\)

\(=6-\frac{1}{6}-\left(5+1\right)-3-\frac{1}{6}\)

\(=\left[6-\left(5+1\right)\right]-\frac{1}{6}-\frac{1}{6}-3\)

\(=0-\frac{1}{6}-\frac{1}{6}-3\)

\(=\frac{-1}{6}-\frac{1}{6}-3\)

\(=\frac{-10}{3}\)

\(\left(\frac{-1}{\frac{1}{2}}:1,25\right)+\left(\frac{10}{\frac{3}{7}}:\frac{5}{\frac{3}{14}}\right)\)

\(=\left(-2:1,25\right)+\left(\frac{70}{3}:\frac{70}{3}\right)\)

\(=\frac{-8}{5}+1=\frac{-3}{5}\)

giúp mình với

\(a,\dfrac{7}{9}-\dfrac{2}{7}+\dfrac{2}{3}+\dfrac{4}{7}\\ =\left(\dfrac{7}{9}+\dfrac{6}{9}\right)+\left(\dfrac{4}{7}-\dfrac{2}{7}\right)\\ =\dfrac{13}{9}+\dfrac{2}{7}\\ =\dfrac{109}{63}\\ b,13,8+7-5,25+4,25\\ =\left(13,8+7\right)-\left(5,25-4,25\right)\\ =20,8-1\\ =19,8\)

a \(\left(\dfrac{4}{7}-\dfrac{2}{7}\right)+\left(\dfrac{7}{9}+\dfrac{2}{3}\right)=\dfrac{2}{7}+\left(\dfrac{7}{9}+\dfrac{6}{9}\right)=\dfrac{2}{7}+\dfrac{15}{9}=\dfrac{2}{7}+\dfrac{5}{3}=\dfrac{6}{21}+\dfrac{35}{21}=\dfrac{41}{21}\)

b \(20.8-1=19.8\)

a: \(=\left(1.25\right)^{16}\cdot8^{16}\cdot8=8\cdot10^{16}\)

b: \(=\left(\dfrac{5}{2}\right)^{13}\cdot4^{13}\cdot4^2=10^{13}\cdot4^2\)

c: \(=\left(0.25\right)^4\cdot8^4\cdot8^2=2^4\cdot8^2=64\cdot16=1024\)

d: \(=\left(\dfrac{1}{2}\right)^{15}\cdot2^{18}=2^3=8\)

e: \(=\left(\dfrac{1}{3}\cdot6\right)^7\cdot\left(\dfrac{1}{2}\right)^7\cdot\dfrac{1}{2}=2^7\cdot\left(\dfrac{1}{2}\right)^7\cdot\dfrac{1}{2}=\dfrac{1}{2}\)