(2)PE=PF still holds. As shown in Figure 2, PM⊥OA, PN⊥OB, which are perpendicular to the bisector of ∠AOB, m, n, ∫p, ∴PM=PN (the nature of angular bisector), ∠PME =∞. ，∫∠PEM+∠PEO =∠PEO+∠PFN = 180？

∴∠PEM=∠PFN、∴△PME≌△PNF(AAS)、∴PE=PF