求详解,按公式来做.
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/11/05 16:30:46
求详解,按公式来做.
25^(Log5 2) + 49^(Log7 3) - 100Lg√6
=5^(Log5 2) * 5^(Log5 2) +7^(Log7 3) * 7^(Log7 3) - 10^(lg√6) * 10^(lg√6)
=2 * 2 + 3 * 3 - √6 * √6
=4 + 9 - 6
=7
lg14 - 2lg(7/3) + lg7 - lg8
=lg(14 / (7/3 * 7/3 ) * 7 /8)
=lg((14*7*3*3)/(7*7*8))
=lg(9/4)
=2lg(3/2)
=2lg3-2lg2
=5^(Log5 2) * 5^(Log5 2) +7^(Log7 3) * 7^(Log7 3) - 10^(lg√6) * 10^(lg√6)
=2 * 2 + 3 * 3 - √6 * √6
=4 + 9 - 6
=7
lg14 - 2lg(7/3) + lg7 - lg8
=lg(14 / (7/3 * 7/3 ) * 7 /8)
=lg((14*7*3*3)/(7*7*8))
=lg(9/4)
=2lg(3/2)
=2lg3-2lg2