已知x^2=5,y^n=3,求(xy)^3n

问题描述:

已知x^2=5,y^n=3,求(xy)^3n

(xy)^3n
=x^3n * y^3n
=(x^2)^(3n/2)*(y^n)^3
=5^(3n/2)*3^3
=27* 5^(3n/2)