题目内容
12.log63•log612+(log62)2-27${\;}^{\frac{2}{3}-lo{g}_{3}2}$=-8-${log}_{3}^{2}$.分析 根据对数的运算性质计算即可.
解答 解:log63•log612+(log62)2-27${\;}^{\frac{2}{3}-lo{g}_{3}2}$
=log63•(${log}_{6}^{3}$+${log}_{6}^{4}$)+(log62)2-9-${log}_{3}^{2}$
=${{(log}_{6}^{3})}^{2}$+2${log}_{6}^{3}$${log}_{6}^{2}$+${{(log}_{6}^{2})}^{2}$-9-${log}_{3}^{2}$
=${{(log}_{6}^{3}{+log}_{6}^{2})}^{2}$-9-${log}_{3}^{2}$
=-8-${log}_{3}^{2}$,
故答案为:-8-${log}_{3}^{2}$.
点评 本题考察了对数的运算,熟练掌握运算性质是解题的关键,本题是一道基础题.
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