8
836377


to' hok bit ve~ hinh` thong cam? nha
cho [(R1//R2)nt R3]//R4 biet R1=R2=40 om, R3-R4=20 om ,cddd qua I1+I4=1A. Tinh' U toan` mach?
cho [(R1//R2)nt R3]//R4 biet R1=R2=40 om, R3-R4=20 om ,cddd qua I1+I4=1A. Tinh' U toan` mach?