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    Please see photo. Why can't the answer also be tan(5pi/4 + X) and so on as tan is a recurring cycle graph thingy? The answer in the book is only pi/4 and there was no range given in the question?
    Same for 12d Name:  ImageUploadedByStudent Room1446657121.692179.jpg
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    (Original post by anoymous1111)
    Please see photo. Why can't the answer also be tan(5pi/4 + X) and so on as tan is a recurring cycle graph thingy? The answer in the book is only pi/4 and there was no range given in the question?
    Same for 12d Name:  ImageUploadedByStudent Room1446657121.692179.jpg
Views: 104
Size:  136.6 KB


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    nobody seems to want to help because of the sideways picture....Name:  b9.jpg
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    (Original post by TeeEm)
    nobody seems to want to help because of the sideways picture....Name:  b9.jpg
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    Are you serious?


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    (Original post by anoymous1111)
    Are you serious?


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    looks that way
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    Name:  ImageUploadedByStudent Room1446661292.130618.jpg
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    (Original post by anoymous1111)
    Please see photo. Why can't the answer also be tan(5pi/4 + X) and so on as tan is a recurring cycle graph thingy? The answer in the book is only pi/4 and there was no range given in the question?
    Same for 12d Name:  ImageUploadedByStudent Room1446657121.692179.jpg
Views: 104
Size:  136.6 KB


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    The answer CAN be tan(5pi/4 + X). But there's no point in writing this, because tan(5pi/4 + X) = tan(pi/4 + X).

    The question is just asking you to write the original expression as a single trig expression. It's not saying "there is only one way to do this", but most people would choose the simplest possible form.
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    (Original post by davros)
    The answer CAN be tan(5pi/4 + X). But there's no point in writing this, because tan(5pi/4 + X) = tan(pi/4 + X).

    The question is just asking you to write the original expression as a single trig expression. It's not saying "there is only one way to do this", but most people would choose the simplest possible form.
    Ok thank you!


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    Hey I was doing the same question so you know for 12D the question at the bottom. I know that youre answer is right but how did you get (Sinθ+Pi/4). Why isnt it (Sinθ-Pi/4).
    Thanks!
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    (Original post by Lilly1234567890)
    Hey I was doing the same question so you know for 12D the question at the bottom. I know that youre answer is right but how did you get (Sinθ+Pi/4). Why isnt it (Sinθ-Pi/4).
    Thanks!
    If you look at the double angle formula, sin(A+B) =sinAcosB + sinBcosA.
    In this case you do have sinA + cosA in the brackets therefore it must be sin(A+B).
    If it was sin(A-B) then you would have sinA-cosA in the brackets
    Not great at explaining but hope that helps


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