What is the area of the shape defined by the locus of a point on a circle rolling around another circle?

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What is the area of a shape, which I'm deeming a 'cylicoid', which is defined as follows: Circle A of radius 1 is held stationary. Circle B of radius 1 has a point on its rim which traces a path as it is rolled around circle A. A cyclicoid is the shape enclosed by the path of the point on circle B's rim. It looks roughly like a heart shape.

In parametric terms, a cyclicoid can be shown to be:

x = 2 cos t + cos (2t)

y = 2 sin t + sin (2t)

However, I'm unsure how to integrate this parametric function to find its area. Any ideas on how to do it and what the answer is? Thanks.

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By stokes' theorem, if $\gamma$ is a closed curve in the plane, then the area it encloses is given by$$S=\int dxdy=\int_\gamma ydx.$$