log8(9)=a
8^a=9
2^3a=3^2
3a*lg2=2*lg3
log3(5)=b
3^b=5
b*lg3=lg5
3a*lg2=2*lg5/b=2(1-lg2)/b
(3ab+2)lg2=2
lg2=2/(3ab+2)