Concept:Simplify the integrand using exponent and logarithm rules, then apply the standard integral of an exponential function.Explanation:First, note exloge6=6x because loge6=ln6.Then exln6⋅ex=6x⋅ex=(6e)x.Integrate: ∫(6e)xdx=ln(6e)(6e)x+C.Since ln(6e)=ln6+lne=ln6+1, we get ϕ(x)=1+ln6(6e)x.Note ln6=loge6, so the denominator is 1+loge6. This corresponds to option D.Answer:ϕ(x)=1+loge6(6e)x, i.e., option D.