1.
4^(4x+1)=8^(2x+3)
(2^2)^(4x+1)=(2^3)^(2x+3)
2^(8x+2)=2^(6x+9)
8x+2=6x+9
2x=7
x=3.5
2.
2^x=4^(y+1)
2^x=(2^2)^(y+1)
2^x=2^(2y+2)
x=2y+2…………(1)
27^y=3^(x-1)
(3^3)^y=3^(x-1)
3^(3y)=3^(x-1)
3y=x-1
x=3y+1…………(2)
由(1),(2)得:
2y+2=3y+1
y=1
x=3y+1=4
x-y=4-1=3