Question

For any two complex numbers z1 and z2 , such that |z1|=|z2|= 1 and z1z2≠-1 then show that
z1+z2/1+z1z2
is a real number.​

Answer 1

Step-by-step explanation:

Possible values- 1 and -1 as -1×1 =-1

z1+z2/1+z1z2

Putting z1 and z2 are 1

= 1+1/1+1×1

=2/2

=1

And

Putting z1 and z2 are -1

-1+-1 / 1+-1×-1

=-2/2

=-1

As 1 and -1 are real, it is real