โปรแกรมจะเรียงประโยคให้ฉันได้ทันทีWe need four node voltages, v1, v2, v3, and v4, and it requires
only four out of the five Eqs. (3.4.1) to (3.4.5) to find them. Although
the fifth equation is redundant, it can be used to check results. We can
eliminate one node voltage so that we solve three simultaneous equations
instead of four. From Eq. (3.4.3), v2 = v1 − 20. Substituting this into
Eqs. (3.4.1) and (3.4.2), respectively, gives