For the R-L circuit shown in Fig, the input voltage. v_i(t) = u (t) The current i(t) is

The equivalent inductance measured between the terminals 1 and 2 for the circuit shown in figure, is

A causal LTI system is described by the difference equation $$2y\left[ n \right] = ay\left[ {n - 2} \right] - 2x\left[ n \right] + \beta x\left[ {n - 1} \right].$$ The system is stable only if