 已知8的n次方=5 4的m次方=2,求2的4m减6n的次方

Question

如题所述

Answer 1

Answer 2

8^n=5，则2^3n=5;4^m=2，则2^2m=2
于是2^(4m-6n)=2^4m÷2^6n=(2^2m)^2÷(2^3n)^2=2*2/5*5=4/25