Choosing the Limits on the Convolution Integral

This short paper offers a convenient method for determining the smallest interval of integration on the convolution integral. Two functions to be convolved are described, analytically, with the aid of step functions. These functions are then substituted into the general form of the convolution integral, and the integrand containing the step functions is interpreted to find the limits. The paper contains a table listing possible combinations of functions to be convolved and the resulting limits on the integral.