An op-amp is fed from a signal source through resistance R1. If it is – McqOptions

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1.	An op-amp is fed from a signal source through resistance R1. If it is to work as sign changer, the feedback resistance Rf should be
A.	equal to R1
B.	twice R1
C.	half R1
D.	either (b) or (c)
Answer» B. twice R1

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