以二为底五的对数+以四为底0.2的对数)乘以(以五为底二的对数+以二十五为底0.5的对数)=(log2 5+log4 0.2)(log5 2+log25 0.5)=(log2 5+log2 0.2/log2 4)(log5 2+log5 0.5/log5 25)=(log2 5+log2 0.2/log2 2²)(log...