Results 1 to 4 of 4

Math Help - Imaginary Numbers?

  1. #1
    Newbie
    Joined
    Mar 2010
    Posts
    1

    Smile Imaginary Numbers?

    I don't understand these math problems and i have get them done by tomorrow. btw they are imaginary numbers, so i squared is replaced with 1, i believe.

    (7+7i)^2


    2i/1+2i


    -6+4i/1+4i

    Thanks so much in advance.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,394
    Thanks
    1478
    Awards
    1
    Quote Originally Posted by matherrsingerr View Post
    (7+7i)^2

    2i/1+2i
    -6+4i/1+4i
    For the first one: (a+bi)^2=(a^2-b^2)+(2ab)i

    For the second just understand that \frac{1}{a+bi}=\frac{a-bi}{a^2+b^2}.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by matherrsingerr View Post
    I don't understand these math problems and i have get them done by tomorrow. btw they are imaginary numbers, so i squared is replaced with 1, i believe.

    [snip]
    No. i^2 = -1.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Mar 2010
    Posts
    18
    [LaTeX ERROR: Convert failed] - Treat it like a normal polynomial, but whn you get an i^2, replace with -1.

    [LaTeX ERROR: Convert failed] - Use the complex conjugate of the denominator and multiply both top and bottom by that conjugate. (Complex Conjugate is given by taking the complex statement, keeping the real parts idenitcal and changing the sign of the negative part).

    Example: [LaTeX ERROR: Convert failed] -> [LaTeX ERROR: Convert failed] -> [LaTeX ERROR: Convert failed] -> [LaTeX ERROR: Convert failed] -> [LaTeX ERROR: Convert failed]
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Imaginary numbers/complex numbers
    Posted in the Algebra Forum
    Replies: 7
    Last Post: August 25th 2009, 11:22 AM
  2. Imaginary Numbers
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: November 19th 2008, 04:15 PM
  3. Imaginary Numbers
    Posted in the Algebra Forum
    Replies: 3
    Last Post: April 21st 2008, 09:58 PM
  4. Imaginary Numbers
    Posted in the Math Topics Forum
    Replies: 4
    Last Post: December 13th 2007, 12:59 PM
  5. Complex Numbers- Imaginary numbers
    Posted in the Algebra Forum
    Replies: 2
    Last Post: January 24th 2007, 12:34 AM

Search Tags


/mathhelpforum @mathhelpforum