Question

giúp mink giải vs

Answer 1

TH1: \(R1ntR2=>Rtd=R1+R2=90\left(om\right)\left(1\right)\)

TH2: \(R1//R2=>Rtd=\dfrac{R1.R2}{R1+R2}=20\left(om\right)\left(2\right)\)

(1)(2)=>hệ pt: \(\left\{{}\begin{matrix}R1+R2=90\\\dfrac{R1.R2}{R1+R2}=20\end{matrix}\right.=>\left[{}\begin{matrix}\left\{{}\begin{matrix}R1=30\left(om\right)\\R2=60\left(om\right)\end{matrix}\right.\\\left\{{}\begin{matrix}R1=60\left(om\right)\\R2=30\left(om\right)\end{matrix}\right.\end{matrix}\right.\)

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