Given an acute △ABC whose orthocenter is denoted by H. A line ℓ passes H and intersects AB,AC at P,Q such that H is the mid-point of P,Q. Assume the other intersection of the circumcircle of △ABC with the circumcircle of △APQ is X. Let C′ is the symmetric point of C with respect to X and Y is the another intersection of the circumcircle of △ABC and AO, where O is the circumcenter of △APQ. Show that CY is tangent to circumcircle of △BCC′.
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