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Real parts, imaginary parts, moduli and arguments

Let z=2+i3−iz=\dfrac{2+i}{3-i}. Without using a calculator, find the real and imaginary parts of

(a) 1+z1−z\dfrac{1+z}{1-z},

(b) z+1zz+\dfrac1z.

Hence, find the modulus and argument of 1+z1−z\dfrac{1+z}{1-z} and z+1zz+\dfrac1z.

CJC · Discussion · Question 11

Clear the small fractions before rationalising; determine arguments from the final Cartesian forms.

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