The Sagdeev potential method is employed to compute the width of the ion-acoustic solitary wave propagated in a dusty plasma containing three components (dust– ion–electron). The results indicate that the width is a continuous function over the allowable ranges of plasma parameters. The complexity of the resulting equations is an obstacle to the expression of the width function in an explicit form in terms of the parameters. Thus, computer algebra is needed to plot the graph of the width function versus the parameters, which helps us to understand the width changes as the parameters change.
