(2016 USAJMO #5) Let △ABC\triangle ABC be an acute triangle, with OO as its circumcenter. Point HH is the foot of the perpendicular from AA to line BC↔,\overleftrightarrow{BC}, and points PP and QQ are the feet of the perpendiculars from HH to the lines AB↔\overleftrightarrow{AB} and AC↔,\overleftrightarrow{AC}, respectively.

Given that AH2=2⋅AO2,AH^2 = 2\cdot AO^2, prove that the points O,P,O, P, and QQ are collinear.

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