R1=1.6 R2=4 R3=6 R4=12 U=18 B
R23=R2*R3/(R2+R3)=4*6/(4+6)=2.4
R234=R23*R4/(R23+R4)=2.4*12/(2.4+12)=2
Ro=R1+R234=1.6+2=3.6
Io=I1=U/Ro=18/3.6=5 A
U234=Io*R234=5*2=10 B
I2=U234/R2=10/4=2.5 A
I3=U234/R3=10/6=1.67 A
I4=U234/R4=10/12=1.83 A
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Задание 12,81 нет схемы
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