1.\(R_1nt\left(R_2//R_3\right)\)
\(R_{23}=\dfrac{R_2\cdot R_3}{R_2+R_3}=\dfrac{30\cdot30}{30+30}=15\Omega\)
\(R_{TĐ}=R_1+R_{23}=15+15=30\Omega\)
\(I_3=I_2=\dfrac{U_2}{R_2}=\dfrac{6}{30}=0,2A\Rightarrow I_1=I_{23}=0,2+0,2=0,4A\)
2.\(\left(R_1ntR_2\right)//R_3\)
\(R_{12}=R_1+R_2=15+30=45\Omega\)
\(R_{TĐ}=\dfrac{R_{12}\cdot R_3}{R_{12}+R_3}=\dfrac{45\cdot30}{45+30}=18\Omega\)
\(I_1=I_2=\dfrac{U_2}{R_2}=\dfrac{6}{30}=0,2A\)
\(U_3=U_2=6V\Rightarrow I_3=\dfrac{U_3}{R_3}=\dfrac{6}{30}=0,2A\)
\(I_{AB}=I_1+I_3=0,2+0,2=0,4A\)
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