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    Hey I would like some help with these questions.

    1.) x=t/(2t-1) y=t/(t+3)
    2.) x=sin2theta y=costheta.
    3.)x=sintheta +2costheta y=2sintheta +costheta


    For all I need to find the Cartesian form. For the first one I got it down to y=x/(7x-3) and for the second one I got it to be x^2=y^2(4-4y^2). As for the third one I have no answer
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    (Original post by Sylarus)
    Hey I would like some help with these questions.

    1.) x=t/(2t-1) y=t/(t+3)
    2.) x=sin2theta y=costheta.
    3.)x=sintheta +2costheta y=2sintheta +costheta


    For all I need to find the Cartesian form. For the first one I got it down to y=x/(7x-3) and for the second one I got it to be x^2=y^2(4-4y^2). As for the third one I have no answer
    I got the same answer as you for the first and second, I'd reckon those answers are just fine.
    For 3, remember that the sinx/cosx = tanx and you can eliminate sin and cos at the same time!
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    (Original post by Sylarus)
    Hey I would like some help with these questions.

    1.) x=t/(2t-1) y=t/(t+3)
    2.) x=sin2theta y=costheta.
    3.)x=sintheta +2costheta y=2sintheta +costheta


    For all I need to find the Cartesian form. For the first one I got it down to y=x/(7x-3) and for the second one I got it to be x^2=y^2(4-4y^2). As for the third one I have no answer
    Why don't you get \sin \theta and \cos \theta in terms of x and y then use \sin^2 \theta + \cos^2 \theta = 1?
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    x = sinΘ + 2cosΘ

    y = 2sinΘ + cosΘ

    see what happens with squaring
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    I think this is a duplicate thread - looks awfully familiar.
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    (Original post by ghostwalker)
    I think this is a duplicate thread - looks awfully familiar.
    I was wondering that, I saw you and notnek answer something similar yesterday(?) but I wasn't sure, so I went ahead and replied to it anyway.
 
 
 
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