Dany jest obwód, gdzie R1=a(П), R2=b(П), R3=c(П), R4=5(П)

R1=a Ω
R2=b Ω
R3=c Ω
R4=5 Ω
U=6 V
Ir2=?
Rz123 = R3+(R1*R2)/(R1+R2)
Rz123=c+ab/(a+b)
Ir3=U/Rz123
Ur2=U-Ur3
Ur2=U-Ir3*R3
Ur2=U*(1-R3/Rz123)
Ur2=U*(1-c/(c+ab/(a+b)))
Ir2=Ur2/R2
Ir2=(U/b)*(1-c/(c+ab/(a+b)))
Ir2=(U*a)/(ca+cb+ab)