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Math Help - Trigonometric Equaiton Help Please!

  1. #1
    nee
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    Trigonometric Equaiton Help Please!

    Find the angle in degrees

    0.342Dcosx + hcos(squared)x = 16D(squared) / V(squared)

    V = 60
    D = 80
    h = 2
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    Quote Originally Posted by nee View Post
    Find the angle in degrees

    0.342Dcosx + hcos(squared)x = 16D(squared) / V(squared)

    V = 60
    D = 80
    h = 2

    Is it (16*D)^2 or 16*(D^2)?
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  3. #3
    nee
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    The way it's written in the text is 16D(squared).
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    Quote Originally Posted by nee View Post
    The way it's written in the text is 16D(squared).

    Ok, which one of my 2 ways would you interpret that?
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  5. #5
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by lewisb13 View Post
    Ok, which one of my 2 ways would you interpret that?
    @ nee: meaning, was it 16D^2 or (16D)^2
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  6. #6
    nee
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    exactly
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    So you've got 2x^2+27.36x^2-256/9=0
    Here we are letting x = cos x
    Use the quadratic equation. Youll get 2 numbers. Probably one positive and one negative.

    FOR EXAMPLE you get 5 and -16

    5 = cos x
    -16 = cos x

    Solve for x.
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    x = -14.6508 or x = .97075
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  9. #9
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    13.892 degrees
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  10. #10
    nee
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    Thanks alot, I'll give it a try!
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  11. #11
    nee
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    I keep getting -12.55 and -1.133 which don't give me an angle!?
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    Did you solve the quadratic? Or are those ^^^^ the numbers you got while solving the quadratic?
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  13. #13
    nee
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    Ya I used



    and put the values into:



    I end up with

    x = -27.36 +or- 22.83 / 4

    which gives me

    12.55 and -1.133
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