In mathematics class, Mr. Zhang showed the question: as shown in the figure: △ ABC is an isosceles right triangle, ∠ ACB = 90 °, ab ⊥ BF, point P is any point on BC, and AP ⊥ PF. Is AP equal to PF? If "point P is any point on edge BC" is changed to "point P is any point on extension line of edge CB (except B and C)", other conditions remain unchanged, then is the conclusion still valid? If correct, please draw a graph and write the proof process
(1) The fo ⊥ CB extension line is drawn at o point as shown in the figure. ∵ ABC is isosceles right triangle, ∵ ACB = 90 °, ∵ ABC = 45 °, and ∵ ab ⊥ BF, ∵ FBO = 45 °, ∵ Bo = fo, and ∵ AP ⊥ PF,
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