Question

For an ideal non-inverting operational amplifier having finite gain (A), the ratio of output voltage (v0) to input voltage (vi) is (given R2 is the feedback resistance)

(a) (1+R2/R1)/(1+((1+R2/R1)/A))

(b) (R2/R1)/(((1+R2/R1)/A))

(c) (1+R2/R1)/(((1+R2/R1)/A))

(d) (R2/R1)/(1+((1+R2/R1)/A))

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Asked question is from The Non Inverting Configuration topic in section Operational Amplifiers of Electronic Devices & Circuits

Answer 1

Correct option is (a) (1+R2/R1)/(1+((1+R2/R1)/A))

The best explanation: It is a standard mathematical expression.