xixitui
幼苗
共回答了18个问题采纳率:83.3% 举报
i1+i2-i3=0 ```````````````1
i1+4i3=18 ```````````````2
i2+4i3=9 ````````````````3
由2式-3式得:
i1-i2=9 ·······················4
由1式x4+2式得:
5i1+4i2=18·················5
由4式x4+5式得:
9i1=63 解得:i1=7代入4得:
i2=-2
所以可得:i3=-5
1年前
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