// Exa 1.13 format('v',7); clc; clear; close; // Given data Rf= 250;// in kohm // Output voltage expression, Vo= -5*Va+3*Vb // and we know that for a difference amplifier circuit, // Vo= -Rf/R1*Va + [R2/(R1+R2)]*[1+Rf/R1]*Vb // Comparing both the expression, we get // -Rf/R1*Va= -5*Va, or R1= Rf/5;// in kohm disp(R1,"The value of R1 in kohm") // and R2= 3*R1^2/(R1+Rf-3*R1) disp(R2,"The value of R2 in kohm") // Note : Answer in the book is wrong