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Verify whether the statement is true.

  1. Feb 20, 2012 #1
    1. The problem statement, all variables and given/known data
    2cos^2 4x-1=0

    a)x= pi/16 x=3pi/16


    2. Relevant equations



    3. The attempt at a solution
    a) x=pi/16

    u=cosx
    v=4x
    2u^2 v-1=0
    i'm stuck here
     
    Last edited by a moderator: Feb 20, 2012
  2. jcsd
  3. Feb 20, 2012 #2

    jedishrfu

    Staff: Mentor

    are you solving this equation: 2 * cos^2(4x) - 1 = 0

    first plugin the x=pi/16 --> 4x = pi/4 and so you have 2 * cos^2(pi/4) - 1 = 0

    so what is cos(pi/4)? then square it and solve.
     
  4. Feb 20, 2012 #3

    Mark44

    Staff: Mentor

    What does this mean? I can think of at least two interpretations. Use parentheses to make the meaning clear.
     
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