3^x-4= 27 e^2x-5e^x+6=0 log2-log(x+1)=log(x+2)-log(3x+1) 唔識計.可唔可有步驟教我點計?

1 3^(x－4)= 27
Sol
3^3=27
X－4=3
x=7
2 e^(2x)－5e^x+6=0
Sol
e^(2x)－5e^x+6=0
(e^x－2)(e^x－3)=0
e^x=2 or e^x=3
x=ln2 or x=ln3
3 log2－log(x+1)=log(x+2)－log(3x+1)
Sol
log2－log(x+1)=log(x+2)－log(3x+1)
log2+log(3x+1)=log(x+1)+log(x+2)
2(3x+1)=(x+1)(x+2)
6x+2=x^2+3x+2
x^2－3x=0
x(x－3)=0
x=0 or x=3
x+1>0，x+2>0，3x+1>0
x=0 or x=3

THX~