2^x=4^(y+1) 2^x=2^2(y+1) 所以x=2(y+1) 一试
3^(x-1)=27^y 3(x-1)=3^3y 所以（x-1）=3y 二试
联立求解上边一试 二试 y=1 x=4
xy=4
m^a=5 a=log(m)(5) m^b=2 b=log(m)(2)
m^(3a+2b)=m^3a * m^2b=m^3log(m)(5) * m^2log(m)(2)
=m^log(m)(5)^3 * m^log(m)(2)^2
=(5)^3 *(2)^2
=5000.0