Trouble with complex numbers

The question is this:

I'm not sure if what I am doing is right...

My next step was this:

But I'm not sure what to do after. Is it just simple algebra? Because if it is, I did something really weird and didn't get the answer, which is supposed to be

Any help would be wonderful! Any working would be great, to see where I went wrong.

Re: Trouble with complex numbers

You're doing fine, just multiply out the brackets and write it as for some values x and y. Then in order to find the absolute value, you simply take the square root of . If you picture the complex number on the complex plane, where the x axis corresponds to the real part and the y axis corresponds to the imaginary part, then is simply the hypotenuse of a right angle triangle with horizontal side of length and vertical side of length .

Re: Trouble with complex numbers

Quote:

Originally Posted by

**maybealways** The question is this:

I'm not sure if what I am doing is right...

My next step was this:

You can really simplify things by noting

Thus

Moreover