Paragraph (Questions 7-8): Let the incircle of \(\triangle ABC\) touch sides \(BC, CA, AB\) at \(A_1, B_1, C_1\) respectively. The incircle of \(\triangle A_1B_1C_1\) touches its sides \(B_1C_1, C_1A_1, A_1B_1\) at \(A_2, B_2, C_2\) respectively and so on.Find \(\lim_{n \to \infty} \angle A_n\)
If \sin^{-1}: [-1,1] \to \left[-\frac{\pi}{2}, \frac{\pi}{2}\right] and \cos^{-1}: [-1,1] \to [0, \pi] be two bijective functions, respectively inverses of bijective functions \sin: \left[-\frac{\pi}{2}, \frac{\pi}{2}\right] \to [-1,1] and \cos: [0,\pi] \to [-1,1], then \sin^{-1}x + \cos^{-1}x is