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Sequences Q (C2)

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    (Original post by f1mad)
    Read the question carefully.

    "k in terms of t".

    I believe this would mean it only wants k in terms of t, not any other constant.
    So how will i do it?
    Can you please help me on doing this.
    I have never done such questions.
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    (Original post by raheem94)
    So how will i do it?
    Can you please help me on doing this.
    I have never done such questions.
    Neither have I. It's about using what you know.

    The cos graph has a period of 360. This is affected by the scale factor in the variable t, given by the constant k.

    Hence kt= 360

    -> k= 360/t

    For the second bit:

    You know that the constant k specifies the number of oscillations in a unit time interval-> clearly for one second it would be k/360.
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    (Original post by f1mad)
    Neither have I. It's about using what you know.

    The cos graph has a period of 360. This is affected by the scale factor in the variable t, given by the constant k.

    Hence kt= 360

    -> k= 360/t

    For the second bit:

    You know that the constant k specifies the number of oscillations in a unit time interval-> clearly for one second it would be k/360.
    Thanks .

    The equation given in the question is, y=asin(kt+c).

    I know sin also has a period of 360 but why both you and the OP are talking about cos having a period of 360 rather than sin.
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    (Original post by raheem94)
    Thanks .

    The equation given in the question is, y=asin(kt+c).

    I know sin also has a period of 360 but why both you and the OP are talking about cos having a period of 360 rather than sin.
    Well it hardly matters; sin and cos have the same periodicity.

    For some reason I had 'y=acos(kt+c)' written down. Hmm..
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    (Original post by f1mad)
    Well it hardly matters; sin and cos have the same periodicity.

    For some reason I had 'y=acos(kt+c)' written down. Hmm..
    No problem.

    The reason i got confused was that both you and OP were talking about cos rather than sin.

    I understand it now, thanks for your help.

    I was looking at the question from a different angle, hence i was struggling with it.
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    (Original post by raheem94)
    Thanks .

    The equation given in the question is, y=asin(kt+c).

    I know sin also has a period of 360 but why both you and the OP are talking about cos having a period of 360 rather than sin.
    Sorry that was just an error, I must have had cos on the brain. Thanks to f1mad for clearing this up, I was having trouble explaining.
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    (Original post by vinvinvin)
    Sorry that was just an error, I must have had cos on the brain. Thanks to f1mad for clearing this up, I was having trouble explaining.
    No problem. :cool:
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    (Original post by vinvinvin)
    Sorry that was just an error, I must have had cos on the brain. Thanks to f1mad for clearing this up, I was having trouble explaining.
    I get it now, thanks for your help.

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