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How does this distribute?

  1. Feb 19, 2010 #1
    Let's say I have an expression like this.


    Does cos45 get multiplied into just the numerator terms or do I also distribute it to the denominator as well?
  2. jcsd
  3. Feb 19, 2010 #2
    Only the numerator. Think of it as cos(45)/1 so that cos(45) multiplies the numerator and 1 multiples the denominator.

    Also, notice that cos(45) equals something simple.
  4. Feb 19, 2010 #3


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    Multiplying into the numerator and the denominator would give you [tex]\frac{cos(45)(601-148)}{cos(45)sin(21.8)}[/tex] and the cosines would cancel which is not what you want.
  5. Feb 19, 2010 #4
    Ok, thanks guys.
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