─ We present the derivation of new closed-form equations for the probability density function (PDF) and cumulative distribution function (CDF) of the product of the ratio of α-µ variates and the gamma variate. These findings have implications for the performance analysis, modeling, and simulation of cooperative diversity systems in fading situations where the signal envelope is influenced by rapid and slow fading. In the presented model fast fading affects the envelope of co-channel interference in this system also. A particular special case of the α-µ distributed variable (Rayleigh, Weibull, and Nakagami-m distributed variables), in several different transmission contexts is modeled. Theoretical results are supplemented by numerical results that are visually depicted.