R ri,+r 3 +R1=0(1) 4B Re R R2i2+12 C -Ri5=0(2)Rr1a R 343+Ri Rai +Ri4=0(3) 回路ACDA D ri-ri tu 2-lx1+R;i1=0 (1)+(2)+(3)回路ACDA R 1+ us1- B R 2+us2- A C R 5 R 4 R 6 R3 D i 1 i4 i6 i3 i5 i 0 ( 3 ) 2 4 4 3 3 6 6 + = +R i R i R i 0 ( 1 ) 1 1 4 4 5 5 1 + = − + − R i R i R i u s 0 ( 2 ) 5 5 6 6 2 2 2 − = − − + R i R i R i u s ( 1 ) ( 2 ) ( 3 ) 0 3 3 2 2 2 1 1 1 + + R i − R i + u s − u s + R i =