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Homework Help: Trig Help

  1. Jan 23, 2005 #1
    OK, I worked through an assignment wanting me to rewrite formulas. However two problems are driving me crazy.

    sin(x + (pi/6))
    I get (sqrt(3)/2)sinX + (1/2)cosX
    not really too simplified.

    (sin^2(2x))(cos^2(2x))
    ((1-cos4x)/2) ((1+cos4x)/2)
    (1-cos^2(4x))(1/4)
    [((2/2)-((1+cos8x)/2)](1/4)
    ((1+cos8x)/4)(1/4)
    (1 + cos8x)(1/16)
    //When I plug numbers in I do not get a valid solution for the original equation so I messed up somewhere.

    Any guidance is appreciated. Thank you for your time and knowledge. Also, congratulations this site has grown a lot since my old days of getting on about everyday. Job got in the way and all.
     
  2. jcsd
  3. Jan 23, 2005 #2

    dextercioby

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    Science Advisor
    Homework Helper

    The first one cannot be simplified indeed...

    The second is
    [tex] \sin^{2}2x\cos^{2}2x [/tex]

    ,or i didn't understant it??

    HINT:
    Use
    [tex] \sin 2u=2\sin u\cos u [/tex]

    Daniel.
     
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