Q7. (a) Zin N RM ww ww R w RM RM www R www www R Z W RM ww Z Figure-Q7 (a) R2 Show that the input impedance of the circuit in Figure-Q7 (a) is, Zin = (12Marks) (b) Figure-Q7 (b) shows an operational amplifier application in a Schmitt trigger circuit. Find the lower and upper trigger levels. Hence draw the hysteresis loop. (Assume that the output switches between +15V and -15V) Vin (8Marks) + 5kQ ww 10ΚΩ Vo +6V Figure-Q7 (b)