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Thread: x^i?

  1. #1 x^i? 
    Member pienapple27's Avatar
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    What does it mean to raise a number to sqrt(-1), aka "i"?
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  2. #2  
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    .
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  3. #3  
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    why does xi equal eiln(x)? and how do I post those pretty mathematical letters?
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  4. #4  
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    Have you studied logarithms?
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  5. #5  
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    I know than ln(x) means eln(x) = x, but don't know how to related xi and eiln(x)
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  6. #6  
    btr
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    You can derive this from the familiar laws of exponents.

    You know that , so you just apply that law in the special case that and , to obtain (recall that ).
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  7. #7  
    btr
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    The pretty mathematical letters are , by the way.

    LaTeX - Wikipedia, the free encyclopedia
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  8. #8  
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    Oh, now it just sounds so simple, I don't know why I didn't figure it out! Thx! Also, how do I use this "LaTeX" thingy?
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  9. #9  
    btr
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    You use the [tex]...[/tex] tags.

    For example, if you write

    [tex]\displaystyle ax^2 + bx + c = 0 \Rightarrow x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}[/tex]

    it will render as




    Edited to add: You don't really need the \displaystyle bit, it just makes the fraction render more attractively. Without you'd get this:

    LaTeX code: [tex]ax^2 + bx + c = 0 \Rightarrow x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}[/tex]

    Rendered output:
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  10. #10  
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    nice! thx!
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