三道数学填空题!(1)[(log(4)(3)+log(8)(3)][log(3)(2)+log(9)(8)]=(2)已知

三道数学填空题!
(1)[(log(4)(3)+log(8)(3)][log(3)(2)+log(9)(8)]=
(2)已知f(x)的定义域为(1/2,8],则f(2^x)的定义域是__.
(3)已知f(x)是R上不恒为零的函数,且对任意的a,b∈R都满足f(ab)=af(b)+bf(a),则f(1)的值是__.