Two resistors R1,R2R_1, R_2R1,R2 are in parallel. If R1=10,R2=20R_1 = 10, R_2 = 20R1=10,R2=20, and dR1/dt=1,dR2/dt=−1dR_1/dt = 1, dR_2/dt = -1dR1/dt=1,dR2/dt=−1, what is dReq/dtdR_{eq}/dtdReq/dt?
19\frac{1}{9}91
−19-\frac{1}{9}−91
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