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    We haven't technically 'learnt' this yet, so are just being asked to 'describe what happens when' but I'm not sure how to word it.

    You start with the curve x^2-3y^3+xy=7.

    1) You replace each x with -x and get this. How do you describe the change?

    2) You go back to the original equation and replace each x with -y and each y with x. How do you describe the change? (I know it's a 90 degree clockwise rotation, but about which point?)

    Thanks.
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    (Original post by yoloman154)
    We haven't technically 'learnt' this yet, so are just being asked to 'describe what happens when' but I'm not sure how to word it.

    You start with the curve x^2-3y^3+xy=7.

    1) You replace each x with -x and get this (first screenshot). How do you describe the change?

    2) You go back to the original equation and replace each x with -y and each y with x. How do you describe the change? (I know it's a 90 degree clockwise rotation, but about which point?)

    Thanks.
    Anyone?
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    (Original post by yoloman154)
    Anyone?
    For the first one, think about how all the points are changing. You're making all the positive x take the place of negative x and vice-versa. i.e:
    Spoiler:
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    a flip in the y-axis.
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    (Original post by Zacken)
    For the first one, think about how all the points are changing. You're making all the positive x take the place of negative x and vice-versa. i.e:
    Spoiler:
    Show
    a flip in the y-axis.
    Of course; now you say it, that makes a lot of sense. My spatial awareness is terrible, so 'seeing things' sometimes takes a while. I really appreciate your help!

    EDIT: Also, WOW Cambridge Maths! Well done! I imagine Warwick are jealous...
 
 
 
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Updated: August 29, 2016
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