Murakkab masalalar: ichki chizilgan burchaklar

$\begin{array}{rl}\text{Aylana uzunligi}& =2\pi r\\ & =2\pi (12)\\ & =24\pi \end{array}$‍

$\begin{array}{rl}{\displaystyle \frac{\text{yoy uzunligi}}{\text{aylana uzunligi}}}& ={\displaystyle \frac{\text{yoyning gradus oʻlchovi}}{\text{aylana gradus oʻlchovi}}}\\ \\ \\ {\displaystyle \frac{\left({\displaystyle \frac{68}{15}}\pi \right)}{24\pi }}& ={\displaystyle \frac{\text{yoyning gradus oʻlchovi}}{{360}^{\circ }}}\\ \\ \\ \text{yoyning gradus oʻlchovi}& ={\displaystyle \frac{68}{15}}\pi \cdot {\displaystyle \frac{{360}^{\circ }}{24\pi }}\\ \\ \\ & ={68}^{\circ }\end{array}$‍

$\begin{array}{rl}\text{Aylana uzunligi}& =2\pi r\\ & =2\pi (4)\\ & =8\pi \end{array}$‍

$\begin{array}{rl}{\displaystyle \frac{\text{yoy uzunligi}}{\text{aylana uzunligi}}}& ={\displaystyle \frac{\text{yoyning radian oʻlchovi}}{\text{aylananing radian oʻlchovi}}}\\ \\ \\ {\displaystyle \frac{\text{yoyning uzunligi}}{8\pi }}& ={\displaystyle \frac{\left({\displaystyle \frac{4}{5}}\pi \right)}{2\pi }}\\ \\ \\ \text{yoyning uzunligi}& ={\displaystyle \frac{4\pi }{5}}\cdot {\displaystyle \frac{8\pi }{2\pi }}\\ \\ \\ & ={\displaystyle \frac{16}{5}}\pi \end{array}$‍