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    how do i solve this equation? i tried to get tan already?
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    You'd have to combine the 2 trig functions using the R formula if you want.
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    \theta = theta =/= feta

    Almost as bad as that other thread where \lambda was said to be lavender
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    (Original post by thekidwhogames)
    You'd have to combine the 2 trig functions using the R formula if you want.
    More commonly known as the Harmonic Addition Theorem.
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    (Original post by MR1999)
    More commonly known as the Harmonic Addition Theorem.
    Yes that's true but most A level students remember it by 'R formulae' as I believe that's what it's often referred to as.
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    (Original post by thekidwhogames)
    Yes that's true but most A level students remember it by 'R formulae' as I believe that's what it's often referred to as.
    yhh i have actually been taught this! how would i apply it here?
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    (Original post by mansnothot)
    yhh i have actually been taught this! how would i apply it here?
    Use it to combine the 2 trig functions. Do you know the identity?
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    (Original post by thekidwhogames)
    Use it to combine the 2 trig functions. Do you know the identity?
    yes its like R(theta+alpha) or Rcos(theta+alpha) right?
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    (Original post by mansnothot)
    yes its like R(theta+alpha) or Rcos(theta+alpha) right?
    Your original problem was. 2cos(x) + sin(x) = 1. R = root of 2^2 + 1^2 meaning R=root 5. Alpha = arc tan (1/2). Plug this into your calculator. If you want it into a single cosine function: AcosX + BsinX = Rcos(X-alpha).


    2cosfeta+sinfeta=1 watched
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    (Original post by thekidwhogames)
    Your original problem was. 2cos(x) + sin(x) = 1. R = root of 2^2 + 1^2 meaning R=root 5. Alpha = arc tan (1/2). Plug this into your calculator. If you want it into a single cosine function: AcosX + BsinX = Rcos(X-alpha).


    2cosfeta+sinfeta=1 watched
    arc tan (1/2)=0.464.

    The final 2 answers are theta= 1.57 or 5.64 so how would i get these?
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    (Original post by mansnothot)
    arc tan (1/2)=0.464.

    The final 2 answers are theta= 1.57 or 5.64 so how would i get these?
    So the new equation is root 5 cos (x-0.464) =1
    cos(x-0.464) = 1 / root 5

    Now you're solving a simple trig equation. You can use CAST or the graph but essentially:

    x-0.464 = 1.107... or 5.176

    so x = 1.57 or 5.64 (2dp).
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    (Original post by thekidwhogames)
    So the new equation is root 5 cos (x-0.464) =1
    cos(x-0.464) = 1 / root 5

    Now you're solving a simple trig equation. You can use CAST or the graph but essentially:

    x-0.464 = 1.107... or 5.176

    so x = 1.57 or 5.64 (2dp).
    so i got 1.57. how would i use the graph to get the other value? i know u have to look for the value of x and take it away from 2pi or something but i dont get the answer.
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    Feta cheese
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