1. Aşağıdakilerden 1. II. III. IV. A) O B) 1 C) 2 D) 3 E) 4 kaç tanesi fonksiyondur? f: RR f(y) = y² + 1 2y+1 f: N → N f(y) 3 f: N→ R f(y) = f: Z→ Z f(y) = y+1 y+5 = 2y+1 3​