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syntax - Solve Parametric Equation


This seems really easy and I'm probably just messing up on the syntax somewhere (I'm pretty new to Mathematica and I did pour through the Solve page trying to find an answer). I'm basically interested in the intersection points of a parametric equation with a plane at $z=.49$. Furthermore, my parametric equation can undergo a rotation, so I would like the intersection coordinates ($x,y,z$) as a function of rotation angle $\theta$.


Easy enough, so I have my parametric equation and I dot it into my rotation matrix and set it equal to $(x,y,.49)$. My question is what am I doing wrong on the syntax since it doesn't realize I'm setting $\phi$ in the range of $0,2\pi$.


    Solve[{Sin[ϕ], Cos[ϕ], 0.5}.{{Cos[θ], 0, -Sin[θ]}, {0, 1, 
0}, {Sin[θ], 0, Cos[θ]}} == {x, y, 0.49}, {ϕ, 0, 2 π}, {x, y}]

Once again easy syntax question, but I can't figure it out. Thanks!





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