题目内容
8.(1)${0.064^{-\frac{1}{3}}}-{({-\frac{1}{8}})^0}+{16^{\frac{3}{4}}}+{0.25^{\frac{1}{2}}}$;(2)${2^{2+{{log}_2}5}}-{2^{{{log}_2}3{{log}_3}5}}$.
分析 (1)直接利用有理指数幂的运算法则化简求解即可.
(2)利用对数的运算法则化简求解即可.
解答 解:(1)${0.064^{-\frac{1}{3}}}-{({-\frac{1}{8}})^0}+{16^{\frac{3}{4}}}+{0.25^{\frac{1}{2}}}$
=0.4-1-1+23+0.5
=2.5-1+8+0.5
=10;
(2)${2^{2+{{log}_2}5}}-{2^{{{log}_2}3{{log}_3}5}}$
=${2}^{2+{log}_{2}5}-{2}^{{log}_{2}{3}^{{log}_{3}5}}$
=4×5-5=15.
点评 本题考查指数与对数的运算法则的应用,考查计算能力.
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