import math
#Example 6.8")
# Given
#R1 = 10kohm R2 = 50kohm Ri = 500kohm R0 = 0")
#Open loop gain (A) = 10**5")
A = 10**5;
R1 = 10*10**3;
R2 = 50*10**3;
Ri = 500.*10**3;
#From figure 6.11
#Applying KCL equation at node B
#(v1+vd)/10+ (v2+vd)/50+ vd/500 = 0 (1)")
#Since R0 = 0
#v2 = A*vd")
#Solving for vd
#vd = 10**-5*v2 (2)")
#Substituting (2) in (1) we get
print "v2/v1 = %d"%(-5)
import math
# Given
#R1 = 1 ohm;R2 = 1/2 ohm;R3 = 1/4 ohm;R4 = 1/8 ohm")
#Rf = 1 ohm")
#From figure 6.14
#THe output of summing circuit can be written as
#v0 = -((Rf/R1)*v1+(Rf/R2)*v2+(Rf/R3)*v3+......")
#From above equation
#v0 = -(8v4+4v3+2v2+v1)-----------(1)")
#a)")
v1 = 1;
v2 = 0;
v3 = 0;
v4 = 1;
# Calculation and Results
#Substituting in equation (1)
v0 = -(8*v4+4*v3+2*v2+v1)
print "v0 = %dV"%(v0);
#b)")
v1 = 0;v2 = 1;v3 = 1;v4 = 1;
#Substituting in equation (1)
v0 = -(8*v4+4*v3+2*v2+v1)
print "v0 = %dV"%(v0);