Let be a complex number represented by What is the condition for the relationship between x and y such that is a real number? A. xy=1 B. x=y C. D. E. none of them above
I can tell you that the correct answer is D.
If one makes all the conversions to rectangular form, its easy to see that if the fraction is real.
That is the same as thus the answer is .
It should be noted that if is also a solution.