The inverting circuit with the T network in the feedback
Chapter 2, Problem 2.30(choose chapter or problem)
The inverting circuit with the T network in the feedback is redrawn in Fig. P2.30 in a way that emphasizes the observation that R2 and R3 in effect are in parallel (because the ideal op amp forces a virtual ground at the inverting input terminal). Use this observation to derive an expression for the gain by first finding and For the latter use the voltage-divider rule applied to R4 and (R2 || R3).
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