Let denote the origin and let be the circle with center and radius 1 in the Cartesian system of coordinates. Let be a real number from the interval , and let the line intersect the circle at points and . The lines and intersect the line at the points and , respectively. Let denote the locus of such points and as varies over the interval . Prove that there exist points and different from the origin in the plane such that for every there exists a point on line satisfying
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