$R_{1}$
$R_{2}$
$R_{Đ_{1}}=r_{1}$
$R_{Đ_{2}}=r_{2}$
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Sđmđ: $(R_{1}//Đ_{1})nt(R_{3}//Đ_{2})$
$M≡N$
$R_{AM}=\dfrac{R_{1}.r_{1}}{R_{1}+r_{1}}$
$R_{BM}=\dfrac{R_{2}.r_{2}}{R_{2}+r_{2}}$
$R_{tđ}=\dfrac{R_{1}.r_{1}}{R_{1}+r_{1}}+\dfrac{R_{2}.r_{2}}{R_{2}+r_{2}}$
$⇒I=\dfrac{U}{R_{tđ}}$
$⇒U_{1}=I.R_{AM}=\dfrac{U}{R_{tđ}}.R_{AM}$
$U_{2}=\dfrac{U}{R_{tđ}}.R_{BM}$
$⇒I_{1}=\dfrac{U_{1}}{R_{1}}=\dfrac{U.R_{AM}}{R_{1}.R_{tđ}}$
$I_{đ_{2}}=\dfrac{U_{2}}{r_{2}}=\dfrac{U.R_{BM}}{r_{2}.R_{tđ}}$
So sánh $I_{1}$ với $I_{đ_{2}}$
