2的a次方=5的b次方=10
则a=log2(10)
b=log5(10)
则
a分之一+b分之一
=log2(10)分之一+log5(10)分之一
=log10(2)/log10(10)+log10(5)/log(10)
=log10(2)+log10(5)
=log10(2*5)
=log10(10)
=1