Radians

$$\text{Angle in Radians}=\frac{\pi }{180^{\circ }}\cdot \text{Angle in Degrees}$$ $$\text{Angle in Degrees}=\frac{180^{\circ }}{\pi }\cdot \text{Angle in Radians}$$

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$2\pi$ radians = $360^{\circ }$ $\pi$ radians = $180^{\circ }$ $1$ radian = $(\frac{180}{\pi }{)}^{\circ }$

$\frac{180}{\pi }$ radians = $1$ degree

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