`(-1)/2 xx 0,75 + (-1)/2 xx 0,25`
` = (-1)/2 xx ( 0,75 + 0,25)`
`= (-1)/2 xx 1`
`= (-1)/2`
`3/4 xx 11/3 + (-3)/(-4) xx 4/3`
`= 3/4 xx 11/3 + 3/4 xx 4/3`
`= 3/4 xx (11/3 + 4/3)`
`= 3/4 xx 15/3`
`= 3/4 xx 5`
`= 15/4`
`0,7 xx (-5)/(-7) + 0,3 : 7/5`
` = 0,7 xx 5/7 + 0,3 xx 5/7`
`= 5/7 xx ( 0,7 + 0,3)`
`=5/7 xx 1`
`= 5/7`
a)\(-\dfrac{1}{2}\cdot0,75+\left(-\dfrac{1}{2}\right)\cdot0,25=-\dfrac{1}{2}\cdot\dfrac{3}{4}-\dfrac{1}{2}\cdot\dfrac{1}{4}=\dfrac{1}{2}\cdot\dfrac{-3}{4}-\dfrac{1}{2}\cdot\dfrac{1}{4}=\dfrac{1}{2}\cdot\left(\dfrac{-3}{4}-\dfrac{1}{4}\right)=-\dfrac{1}{2}\)
b) \(\dfrac{3}{4}\cdot\dfrac{11}{3}+\left(\dfrac{-3}{-4}\right)\cdot\dfrac{4}{3}=\dfrac{3}{4}\cdot\dfrac{11}{3}+\dfrac{3}{4}\cdot\dfrac{4}{3}=\dfrac{3}{4}\cdot\left(\dfrac{11}{3}+\dfrac{4}{3}\right)=\dfrac{3}{4}\cdot5=\dfrac{15}{4}\)
c) \(0,7\cdot\left(\dfrac{-5}{-7}\right)+0,3:\dfrac{7}{5}=\dfrac{7}{10}\cdot\dfrac{5}{7}+\dfrac{3}{10}\cdot\dfrac{5}{7}=\left(\dfrac{7}{10}+\dfrac{3}{10}\right)\cdot\dfrac{5}{7}=\dfrac{5}{7}\)
a=\(-\dfrac{1}{2}.\left(0,75+0,25\right)=-\dfrac{1}{2}.1=-\dfrac{1}{2}\)
\(b=\dfrac{3}{4}.\dfrac{11}{3}+\dfrac{3}{4}.\dfrac{4}{3}=\dfrac{3}{4}.\left(\dfrac{11}{3}+\dfrac{4}{3}\right)=\dfrac{3}{4}.\dfrac{15}{3}=\dfrac{15}{4}\)
\(c=0,7.\dfrac{5}{7}+0,3.\dfrac{5}{7}=\left(0,7+0,3\right).\dfrac{5}{7}=1.\dfrac{5}{7}=\dfrac{5}{7}\)
a) \(\dfrac{-1}{2}.0,75+\left(\dfrac{-1}{2}\right).0,25\)
= \(\dfrac{-1}{2}.\left(0,75+0,25\right)\)
= \(\dfrac{-1}{2}.1\)
= \(\dfrac{-1}{2}\)
b) \(\dfrac{3}{4}.\dfrac{11}{3}+\left(\dfrac{-3}{-4}\right).\dfrac{4}{3}\)
= \(\dfrac{3}{4}.\dfrac{11}{3}+\dfrac{3}{4}.\dfrac{4}{3}\)
= \(\dfrac{3}{4}.\left(\dfrac{11}{3}+\dfrac{4}{3}\right)\)
= \(\dfrac{3}{4}.\dfrac{15}{3}\)
= \(\dfrac{15}{4}\)
c) 0,7 . \(\dfrac{-5}{-7}+0,3:\dfrac{7}{5}\)
= 0,7 . \(\dfrac{5}{7}\)+ 0,3 . \(\dfrac{5}{7}\)
= \(\dfrac{5}{7}.\left(0,7+0,3\right)\)
= \(\dfrac{5}{7}.1\)
= \(\dfrac{5}{7}\)
a) \(\dfrac{-1}{2}\times0,75+\dfrac{-1}{2}\times0,25=\dfrac{-1}{2}\times\left(0,75+0,25\right)\)
\(=\dfrac{-1}{2}\times1=\dfrac{-1}{2}\)
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b) \(\dfrac{3}{4}\times\dfrac{11}{3}+\dfrac{-3}{-4}\times\dfrac{4}{3}=\dfrac{3}{4}\times\dfrac{11}{3}+\dfrac{3}{4}\times\dfrac{4}{3}\)
\(=\dfrac{3}{4}\times\left(\dfrac{11}{3}+\dfrac{4}{3}\right)\)
\(=\dfrac{3}{4}\times\dfrac{15}{3}\)
\(=\dfrac{3}{4}\times5=\dfrac{15}{4}\)
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c). \(0,7\times\dfrac{-5}{-7}+0,3:\dfrac{7}{5}=0,7\times\dfrac{5}{7}+0,3:\dfrac{7}{5}\)
\(=\left(0,7+0,3\right)\times\left(\dfrac{5}{7}:\dfrac{7}{5}\right)\)
\(=1\times\left(\dfrac{5}{7}\times\dfrac{5}{7}\right)\)
\(=1\times\dfrac{25}{49}=\dfrac{25}{49}\)