A. B is two points on the parabola y ^ 2 = 2px (P > 0), which satisfies OA vertical ob (o is the origin), and proves that the straight line AB always passes a certain point How did you get the answer at the last step? I don't understand Or is there a better solution How to find (Y1 + Y2) * y = 2p (x-2p)?
(Y1 + Y2) * y = 2p (x-2p) if you substitute x = 2p, then y is equal to 0, so it is constant over (2P, 0)
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