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    To be perfectly honest I have no idea what topic this comes under, but anyway here goes:

    Show that the curves y = 3sin\theta + 1 and y=2cos2\theta will intersect when

    2sin2 + 3sin\theta- 1 = 0

    I've spent 20 mins trying to work it out but I have no clue what to do. I haven't seen a question like this before...
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    When do two curves intersect? When they both go through the exact same point.

    How do you work out the 1 point that two curves go through?
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    (Original post by claret_n_blue)
    When do two curves intersect? When they both go through the exact same point.

    How do you work out the 1 point that two curves go through?
    uhh....simultaneous equation?
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    (Original post by Alleykat606)
    uhh....simultaneous equation?
    Yeap
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    (Original post by Alleykat606)
    uhh....simultaneous equation?
    set them equal to each other

    spot that the answer has no cos

    Use a well know identity to change your cos to sin
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    (Original post by claret_n_blue)
    Yeap
    but what does the last equation have to do with it? :confused:
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    (Original post by Alleykat606)
    but what does the last equation have to do with it? :confused:
    That's the answer to the question. You are showing the curves intersect at that point. So after your calculations are complete, you should get that answer.
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    (Original post by claret_n_blue)
    That's the answer to the question. You are showing the curves intersect at that point. So after your calculations are complete, you should get that answer.
    OHHH I get it now. Wording just confused me for a second there. Thanks ever so much!
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    (Original post by Alleykat606)
    OHHH I get it now. Wording just confused me for a second there. Thanks ever so much!
    No worries
 
 
 
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