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\(\frac{2\times 4 \times 8 \times 16}{(log_24)^2 (log_48)^2(log _816)^4}\) = ? |
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Answer» Calculation: \(\frac{2\times 4 \times 8 \times 16}{(log_24)^2 (log_48)^2(log _816)^4}\) ⇒ \(\frac{{2{\rm{\;}} \times 4 \times 8 \times 16}}{{{{({\rm{lo}}{{\rm{g}}_2}4{\rm{\;}} \times {\rm{\;lo}}{{\rm{g}}_4}8{\rm{\;}} \times {\rm{lo}}{{\rm{g}}_8}16)}^2}{\rm{\;}} \times \left( {{\rm{lo}}{{\rm{g}}_4}8 \times {\rm{lo}}{{\rm{g}}_8}16} \right) \times {\rm{lo}}{{\rm{g}}_8}16}}\) We know \(lo{g_{b\;}}a = \frac{{loga}}{{logb}}\) ⇒ \(\frac{{\left( {2 \times 4 \times 8 \times 16} \right)}}{{{{(\frac{{{\bf{log}}4}}{{{\bf{log}}2}} \times \frac{{{\bf{log}}8}}{{{\bf{log}}4}} \times \frac{{{\bf{log}}16}}{{{\bf{log}}8}})}^{2\;}} \times \left( {\frac{{{\bf{log}}8}}{{{\bf{log}}4}} \times \frac{{{\bf{log}}16}}{{{\bf{log}}8}}} \right) \times {\rm{lo}}{{\rm{g}}_8}16}}\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{(lo{g_2}16)}^2} \times \;{\rm{lo}}{{\rm{g}}_4}16 \times {\rm{lo}}{{\rm{g}}_8}16}}\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{(lo{g_2}{2^4})}^2} \times \;{\rm{lo}}{{\rm{g}}_4}{4^2} \times {\rm{lo}}{{\rm{g}}_8}\left( {8 \times 2} \right)}}\) We know \(lo{g_{a\;}}a = 1\;\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{\left( 4 \right)}^2} \times 2 \times {\rm{lo}}{{\rm{g}}_8}\left( {8 \times 2} \right)}}\) We know \(\log \left( {m\; \times n} \right)\; = logm + logn\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{\left( 4 \right)}^2} \times 2 \times \left[ {{\rm{lo}}{{\rm{g}}_8}8 + {\rm{lo}}{{\rm{g}}_8}2} \right]}}\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{\left( 4 \right)}^2} \times 2 \times \left[ {1 + \frac{{{\rm{log}}2}}{{{\rm{log}}8}}} \right]}}\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{\left( 4 \right)}^2} \times 2 \times \left[ {1 + \frac{{{\rm{log}}2}}{{{\rm{log}}{2^3}}}} \right]}}\) ⇒ \(\frac{{2\; \times 4 \times 8 \times 16}}{{{{\left( 4 \right)}^2} \times 2 \times \left[ {1 + \frac{1}{3}} \right]}}\) ⇒ 24 ∴ \(\frac{2\times 4 \times 8 \times 16}{(log_24)^2 (log_48)^2(log _816)^4}\) is 24. |
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