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Math Help - trig equation help leas

  1. #1
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    trig equation help leas

    Solve equation for x 0 - 360 (degrees)

    4sinx + 3cosx = 6
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by gracey View Post
    Solve equation for x 0 - 360 (degrees)

    4sinx + 3cosx = 6
    write 4 \sin x = 6 - 3 \cos x

    now square both sides. what do you get? can you continue? think quadratic equation (note you will need to use a famous trig identity before you can get it into quadratic form. try to change all the sines into cosines)
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  3. #3
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    There are no values of x that satisfy the equation.

    You can use Rcos(x-Q)=4sinx + 3cosx,

    RcosxcosQ+RsinxsinQ = 4sinx + 3cosx

    RcosQ=3
    RsinQ=4

    tanQ=4/3
    R=5

    5cos(x-Q) =6 ... (1)

    Equation 1 does not have have solutions.
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