Plotting complex numbers in z plane

Show how to plot 1/(4+3j) in the complex plane. What is the magnitude and phase shift of this complex number?

Answer 1

[Roger Stafford]

For the magnitude and phase of a complex number use matlab functions ‘abs’ and ‘angle’. (The angle will be in radians from -pi to +pi.) To plot a complex number z, do plot(real(z),imag(z),’y.’).

Note: You can hand-calculate the real and imaginary parts of your particular number using the following trick:

1/(4+3*j) = 1/(4+3*j)*(4-3*j)/(4-3*j) =
       (4-3*j)/(4^2+3^2) = 4/25 - 3/25*j

Answer 2

[KSSV]

z = 1/(1+4*i) ; % multiply and divide by (1-4*i) , MATLAB does it automatically for you 

M = abs(z)    %magnitude
Ph = angle(z) %phase angle
Ph2 = atan2(imag(z),real(z)) %phase angle
% plotting 
figure
 plot(real(z),imag(z),'*r')