有两个电阻R1和R2，已知R1>R2,若将两个电阻并联，总电阻为R。证明：R1/2>R.R2/2

热心网友

数学知识.由于R1R2, 则 R1*R1R1*R2R2*R2 R1*R1+R1*R22*R1*R2R2*R2+R1*R2 R1*(R1+R2)2*R1*R2R2*(R2+R2) R12*R1*R2/(R1+R2)R2 R12RR2即 R1/2RR2/2

热心网友

R=(R1*R2)/(R1+R2),比较大小即可！！