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Homework Help: Trig Help

  1. Nov 6, 2004 #1
    I'm retarded...any help would be much congratulated...and i have two problems that are bugging me fiercing

    Prove the given identity:

    1)
    tan(x)-sin(x)/2tan(x) = sin^2(x/2)



    2)
    sin2x = 1 / tanx + cot2x
     
    Last edited: Nov 7, 2004
  2. jcsd
  3. Nov 6, 2004 #2
    Please show us what you have tried so far.
     
  4. Nov 6, 2004 #3
    Hmmm..that is tough...
    I'm actually having trouble w/ questions similar to this too
     
  5. Nov 6, 2004 #4
    on number 2...wouldn't you try to get both sides equal to "sin2x"?
     
  6. Nov 7, 2004 #5
    1)
    tan(x)-sin(x)/2tan(x) = sin^2(x/2)
    1-sin(x)/2 = sin^2(x/2)

    (That's as far as i've gotten on this one...but i don't know if i'm in the right direction or what to do next?)

    2)
    sin2x = 1 / tanx + cot2x
    2sin(x)cos(x) = ''
    sin(x) * cos(x) * sin(x) = ''

    (The same from #1 applies to this problem)
     
  7. Nov 7, 2004 #6
    can anyone help?
     
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