log對數計算 急!

2.log4_3*log9_5*log125_16
=(log3/log4)*(log5/log9)*(log16/log125)
=[log3/(2log2)]*[log5/(2log3)]*[4log2/(3log5)]
=(1/2)*(1/2)*(4/3)
=1/3

4. 3log4_2+(1/2)log4_25-log4_10
=3log2/log4+(1/2)log25/log4-log10/log4
=3log2/(2log2)+log5/(2log2)-log10(2log2)
=(3log2+log5－log10)/(2log2)
=log(8*5/10)/(2log2)
=log4/(2log2)
=1

6.[log2_5+log4_(1/5)]*[log25_2+log5_(1/4)]
=[log5/log2+log(1/5)/log4]*[log2/log25+log(1/4)/log5]
=[log5/log2－log5/(2log2)]*[log2/(2log5)－log4/log5]
=[2log5/(2log2)－log5/(2log2)]*[log2/(2log5)－4log2/(2log5)]
=[log5/(2log2)]*[－3log2/(2log5)]
=－3/4

https://lh4.googleusercontent.com/-E83pv_Z3KpE/TgHdYiGAElI/AAAAAAAAGKc/OGfAxfwrx48/log1.JPG


圖片參考：https://lh4.googleusercontent.com/-E83pv_Z3KpE/TgHdYiGAElI/AAAAAAAAGKc/OGfAxfwrx48/log1.JPG


2011-06-22 20:24:58 補充：
第2題底都是4

2011-06-22 20:31:38 補充：
https://lh5.googleusercontent.com/-OZS62XlRXlk/TgHgQgS5LJI/AAAAAAAAGKw/9JCJdzhxuac/log1x.JPG
補第2題底都是4
並說明

2011-06-22 20:32:01 補充：
https://lh5.googleusercontent.com/-OZS62XlRXlk/TgHgQgS5LJI/AAAAAAAAGKw/9JCJdzhxuac/log1x.JPG