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Homework Help: Verifying Trig Identities

  1. Jul 12, 2010 #1
    1. The problem statement, all variables and given/known data

    sin^3(x)-cos^3(x)
    sin(x) - cos(x)

    equals

    1 + sin(x) + cos(x)

    2. Relevant equations
    Not sure :/


    3. The attempt at a solution
    Not sure where to even start.
     
  2. jcsd
  3. Jul 12, 2010 #2
    Are you sure that it's 1+sin(x)+cos(x) and not 1+sin(x)cos(x)?

    Use the identity sin^2(x)+cos^2(x)=1.
     
  4. Jul 12, 2010 #3
    Oh yeah, that was it.
     
  5. Jul 12, 2010 #4
    sin^3(x)-cos^3(x)
    -----------------
    sin(x) - cos(x)

    Try factoring the numerator, it may help you.
     
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