问题
解答题
计算求值 (I)0.064
(Ⅱ)lg25+lg5-lg4+lg22. |
答案
(I)0.064
-(-1 3
)0+160.75+0.257 8 1 2
=(0.43)
-1+(24)1 3
+(0.52)3 4 1 2
=0.4-1+8+0.5=
;79 10
(Ⅱ)lg25+lg5-lg4+lg22
=lg25+lg5-2lg2+lg22
=(lg5+lg2)2-2lg5lg2-2lg2+lg5
=1-2lg2(lg5+1)+lg5.