\(\frac{4^2.5.11}{44.20}=\frac{2^4.5.11}{2^2.11.2^2.5}=\frac{2^4.5.11}{2^4.5.11}=1\)
\(\frac{13.15.6}{18.65.7}=\frac{13.3.5.2.3}{2.3^2.13.5.7}=\frac{3^2.2.5.13}{2.3^2.13.5.7}=\frac{1}{7}\)
\(\frac{4^2.5.11}{44.20};\frac{13.15.6}{18.65.7};\frac{7.2.8.5^2}{14.2.5}\)và\(\frac{2^3.3^2.5}{3.2^3.5^3}\)
Ta có : \(\frac{4^2.5.11}{44.20}=\frac{42.5.11}{4.11.4.5}=\frac{4^2.1.1}{4^2.1.1}=1\)
\(\frac{13.15.6}{18.65.7}=\frac{13.3.5.6}{3.6.15.5.7}=\frac{1.1.1.1}{1.1.1.1.7}=\frac{1}{7}\)
\(\frac{7.2.8.5}{14.2.5}=\frac{7.2.2^3.5^2}{2.7.2.5}=\frac{1.1.2^2.5}{1.1.1.1}=\frac{20}{1}\)
\(\frac{2^3.3^3.5}{3.2^3.5^3}=\frac{1.3^2.1}{1.1.5^2}=\frac{9}{25}\)
+) Ta có : \(7=7\)
\(25=5^2\)
\(MC=BCNN\left(7;25\right)=5^2.7=175\)
Khi đó : ................
p/s : kham khảo