section_heading: Sinus, kosinus i tangens višestrukih kutova
paragraph_text: <math>\operatorname{ctg}\,(n{+}1)\theta = \frac{\operatorname{ctg} n\theta\,\operatorname{ctg} \theta - 1}{\operatorname{ctg} n\theta + \operatorname{ctg} \theta}.</math>