题目内容
2.(Ⅰ)计算:1.5${\;}^{-\frac{1}{3}}$×(-$\frac{7}{6}$)0+80.25×$\root{4}{2}$+($\root{3}{2}$×$\sqrt{3}$)6-$\sqrt{(\frac{2}{3})^{\frac{2}{3}}}$的值.(Ⅱ)计算:lg22•lg250+lg25•lg40的值.
分析 (Ⅰ)利用有理数指数幂性质、运算法则求解.
(Ⅱ)利用对数性质、运算法则求解.
解答 解:(Ⅰ)1.5${\;}^{-\frac{1}{3}}$×(-$\frac{7}{6}$)0+80.25×$\root{4}{2}$+($\root{3}{2}$×$\sqrt{3}$)6-$\sqrt{(\frac{2}{3})^{\frac{2}{3}}}$
=$\frac{{2}^{\frac{1}{3}}}{{3}^{\frac{1}{3}}}$×1+${2}^{\frac{3}{4}}$×2${\;}^{\frac{1}{4}}$+4×27-($\frac{2}{3}$)${\;}^{\frac{1}{3}}$
=2+108
=110.
(Ⅱ)lg22•lg250+lg25•lg40
=lg22(2lg5+1)+lg25(2lg2+1)
=2lg22lg5+lg22+2lg25lg2+lg25
=2lg2lg5(lg2+lg5)+lg22+lg25
=lg22+2lg2lg5+lg25
=(lg2+lg5)2
=1.
点评 本题考查对数式、指数式化简求值,是基础题,解题时要认真审题,注意指数、对数的性质和运算法则的合理运用.
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