Note that the coefficient matrix shown in (4.11) is symmetric [the (I , j) and (j , i) element are equal]. This follows from the fact that the conductance between nodes i and j is that between nodes j and i. Symmetry further simplifies writing the node equations. While symmetry will hold as a general rule for all circuits not containing dependent sources, symmetry of the coefficient matrix cannot be counted on in that case, as we shall see in the next example.