Select the true statement about iterations of x2 + c = f(x) when x0 = 1 + i. and c = -i.

This might help you answer the question:

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I don't understand Alan  

Melody....we're just putting x₀ = 1 + i into  x² + c  and evaluating that, first...

So we have

(1 + i)² + (-i)  =   (1 + 2i - i²) - i     = ( 1 + 2i - 1) - i  = i  = x₁

Then, we're putting this result back into x² + c to get x₂ =

(i)² - i = -1 - i  .......then we put this back into x² + c  to get x₃

So on and so forth......and as Alan notes.....it sets up a repeating "2 cycle" pattern

The question mentions interations so I suppose this is the correct interpretation 

BUT

where does it say in the question that        $$x_n=f(x_{(n-1)})$$

all I see is that   $$f(x)=x^2-i$$

I can certainly see that   $$x_0=1+i$$

I am completely unfamiliar with this wording (notation).