Verified answer

I1 = 0,02 A     U1 = 5,25 B

I2 = 0,005 A  U2 = 3,75 B

I3 = 0,015A    U3 = 3,75 B

Verified answer

U=9 B    R1=262.5 Ом    R2=750 Ом    R3=250 Ом  

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R23=R2*R3/(R2+R3)=750*250/(750+250)=187.5 Ом

R=R1+R23=262.5+187.5=450 Ом  (общее сопротивление цепи)

I=I1=U/R=9/450=0.02 A

U1=I1*R1=0.02*262.5=5.25 B

U2=U3=I*R23=0.02*187.5=3.75 B

I2=U2/R2=3.75/750=0.005 A

I3=U3/R3=3.75/250=0.015 A

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