\(\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}=\frac{2^{29}.3^{18}\left(5.2-9\right)}{2^{28}.3^{18}\left(5.3-7.2\right)}=\frac{2.1}{1}=2\)
\(\frac{5\cdot2^{30}\cdot3^{18}-2^{29}\cdot3^{20}}{5\cdot2^{28}\cdot3^{19}-7\cdot2^{29}\cdot3^{18}}\)
\(\frac{2^{28}\cdot3^{18}\left(5\cdot2^2-2\cdot3^2\right)}{2^{28}\cdot3^{18}\left(5\cdot3-7\cdot2\right)}\)
\(\frac{5\cdot2^2-2\cdot3^2}{5\cdot3-7\cdot2}\)
\(\frac{5\cdot4-2\cdot9}{15-14}\)
\(\frac{20-18}{1}\)
\(\frac{2}{1}=2\)
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