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    So I'm stuck on this question for Core 4. I need to find the cartesian equation of the parametric equations:

    X = 3cos^2(t)

    Y= sin(2t)

    In the form Y^2= f(X)

    Obviously I don't want people to just tell me the answer. If it wasn't for the 2t in the equation for Y it would be straightforward but I just cannot see where to start.


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    Use the double angle formula.
    sin 2t = 2 sin(t) cos(t)
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    (Original post by TheMightyAugur)
    So I'm stuck on this question for Core 4. I need to find the cartesian equation of the parametric equations:

    X = 3cos^2(t)

    Y= sin(2t)

    In the form Y^2= f(X)

    Obviously I don't want people to just tell me the answer. If it wasn't for the 2t in the equation for Y it would be straightforward but I just cannot see where to start.


    Posted from TSR Mobile
    As said above use the double angle formula for sin(2x) and then try using sin^2(x) + cos^2(x) = 1 to get Y^2 in terms of cos^2(x) and hopefully you'll be able to figure out the rest from there


    Posted from TSR Mobile
 
 
 
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Updated: February 5, 2017
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