详细讲解一下这道题---**Extraction Content:** **Question 17:** 如图, 点P是△ABC内一点, PB=PC, ∠ABP=∠ACP. 求证: ∠APB=∠APC. 小虎的证明过程如下: **小虎的证明过程:** 证明: 在△ABP和△ACP中, { PB = PC { ∠ABP = ∠ACP { AP = AP ∴ △ABP ≌ △ACP. (第一步) ∴ ∠APB = ∠APC. (第二步) **(1) 小虎同学的证明过程中, 第一步出现错误;** **(2) 请写出正确的证明过程.** **Chart Description:** * **Type:** Geometric figure (Triangle with an internal point). * **Main Elements:** * A triangle ABC with vertices labeled A, B, and C. * A point P is located inside the triangle. * Line segments connect P to A, B, and C, forming triangles ABP, BCP, and ACP. * Segment PB is marked with a single tick mark, and segment PC is marked with a single tick mark, indicating PB = PC. * Angle ∠ABP (angle at B formed by lines BA and BP) is marked with a single arc, and angle ∠ACP (angle at C formed by lines CA and CP) is marked with a single arc, indicating ∠ABP = ∠ACP. * Line segment AP is present.