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locus of points such 3 points are collinear, in space (Chile 2016 L2 P6)

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May 31, 2019
geometryLocus3D geometryLocus problemscollinear

Problem Statement

Let P1P_1 and P2P_2 be two non-parallel planes in space, and AA a point that does not It is in none of them. For each point XX, let X1X_1 denote its reflection with respect to P1P_1, and X2X_2 its reflection with respect to P2P_2. Determine the locus of points XX for the which X1,X2X_1, X_2 and AA are collinear.