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\(\frac{3.6+2.9.5-18.\left(-4\right)}{7.\left(-7\right)+12.\left(-7\right)+7}=\frac{18+18.5-18.\left(-4\right)}{\left(-7\right).\left(7+12\right)+7}\)
\(=\frac{18\left[1+5-\left(-4\right)\right]}{\left(-7\right).19+7}=\frac{18.10}{7.\left(-19\right)+7}\)
\(=\frac{180}{7\left[\left(-19\right)+1\right]}=\frac{180}{-126}=\frac{=10}{7}\)
\(A=\frac{1}{\left(a-b\right)\left(a-c\right)}+\frac{1}{\left(b-c\right)\left(b-a\right)}+\frac{1}{\left(c-a\right)\left(c-b\right)}\)
\(A=\frac{-b+c}{-\left(a-b\right)\left(a-c\right)\left(b-c\right)}+\frac{-c+a}{-\left(a-b\right)\left(a-c\right)\left(b-a\right)}+\frac{-a+b}{-\left(a-b\right)\left(a-c\right)\left(b-c\right)}\)
\(A=\frac{-b+c-c+a-a+b}{-\left(a-b\right)\left(a-c\right)\left(b-c\right)}\)
\(A=\frac{0}{-\left(a-b\right)\left(a-c\right)\left(b-a\right)}\)
A = 0
a) \(\frac{-1}{24}-\left[\frac{1}{4}-\left(\frac{1}{2}-\frac{7}{8}\right)\right]\)
= \(\frac{-1}{24}-\left[\frac{6}{24}-\left(\frac{12}{24}-\frac{21}{24}\right)\right]\)
= \(\frac{-1}{24}-\left[\frac{6}{24}-\frac{-9}{24}\right]\)
= \(\frac{-1}{24}-\frac{15}{24}\)
= \(\frac{-16}{24}\) = \(\frac{-2}{3}\)
b) \(\left(\frac{5}{7}-\frac{7}{5}\right)-\left[\frac{1}{2}-\left(-\frac{2}{7}-\frac{1}{10}\right)\right]\)
= \(\left(\frac{50}{70}-\frac{98}{70}\right)-\left[\frac{35}{70}-\left(-\frac{20}{70}-\frac{7}{70}\right)\right]\)
= \(\frac{-48}{70}-\left[\frac{35}{70}-\left(-\frac{20}{70}-\frac{7}{70}\right)\right]\)
= \(\frac{-48}{70}-\left[\frac{35}{70}-\frac{-27}{70}\right]\)
= \(\frac{-48}{70}-\frac{62}{70}\)
= \(\frac{-110}{70}=\frac{-11}{7}\)
a) \(\frac{3.6+2.9.5+18.\left(-4\right)}{7.\left(-7\right)+12.\left(-7\right)+7}\)=\(\frac{18+18.5+18.\left(-4\right)}{-7.\left(7+12-1\right)}\)=\(\frac{18.\left(1+5-4\right)}{-7.18}\)=\(\frac{18.2}{18.\left(-7\right)}=\frac{-2}{7}\)
b) \(\frac{2.3.4.5.6-3.4.5.6.7}{2.4.6-4.6.8}=\frac{3.4.5.6.\left(2-7\right)}{4.6.\left(2-8\right)}\)=\(\frac{3.5.\left(-5\right)}{\left(-6\right)}=\frac{-25}{-2}=\frac{25}{2}\)
a)\(\frac{3.6+2.9.5+18.\left(-4\right)}{7.\left(-7\right)+12.\left(-7\right)+7}\)
\(=\frac{18+18.5+18.\left(-4\right)}{7.\left(-7\right)+\left(-12\right).7+7}\)
\(=\frac{18.\left(1+5+-4\right)}{7.\left(-7+-12+1\right)}\)
\(=\frac{15.2}{7.\left(-18\right)}\)
\(=\frac{3.5.2}{7.2.3.-3}\)
\(=\frac{5}{-21}\)
b) \(\frac{2.3.4.5.6-3.4.5.6.7}{2.4.6-4.6.8}\)
\(=\frac{3.4.5.6.\left(2-7\right)}{4.6.\left(2-8\right)}\)
\(=\frac{3.4.5.6.\left(-5\right)}{4.6.\left(-3\right)}\)
\(=\frac{3.5.\left(-5\right)}{\left(-3\right)}\)
\(=\frac{-75}{\left(-3\right)}\)
\(=25\)