A major advantage of active filters is that they can be realized without using

The circuit shown in Figure, acts as a ... and for the given inputs, its output voltage is . . . . . $$V.$$

A non inverting op - amp amplifier is shown in figure. The o/p voltage is

Let the magnitude of the gain in the inverting op - amp amplifier circuit shown be $$x$$ with switch $${S_1}$$ open. When the switch $${S_1}$$ is closed, the magnitude of gain becomes.