如题所述
节点电压法:
(1/2 + 1/2 + 1/2) * U = 12/2 + 20/2 + 6 * i1
i1 = (12 - U) / 2
解得:
U = 104/9 V
外加电源法:
i1 = - Us / 2
7 * i1 + i = Us / 1
i = Us * 9/2
R = Us / i
= 2/9 Ω
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