What is an Imaginary Number?

[Mohammad Hassan Murad]

In our college mathematics probably we all have learned about the imaginary number. We were simply introduced i as a number. Our traditional introduction to imaginary number does not make us see the inner beauty. And it does not fascinate us. Have we ever thought about imaginary number as follows?
1. Is imaginary number a number?
2. What kind of number is i?
3. Where did the name imaginary come from?
4. Is it really an imaginary number? If yes then how did this number get involved into the real mathematics?
5. Can imaginary number do the same thing or different thing as real number do or more?
British mathematical physicist Sir Roger Penrose calls i magic number. What is magical about i?

I am preparing an article on this beautiful fascinating subject and hope to post it soon.

[anirban]

1. Is imaginary number a number?
2. What kind of number is i?
3. Where did the name imaginary come from?
4. Is it really an imaginary number? If yes then how did this number get involved into the real mathematics?
5. Can imaginary number do the same thing or different thing as real number do or more?
[/quote]

Lots of question..... This post makes me curious....eagerly waiting for article with the answer of these questions