Problem
Rewrite \( -75^{\prime} \) in radian measure.
Solution
Step 1 ：\( -75^{\prime} \rightarrow -\frac{75}{60} \text{ degrees} \)
Step 2 ：\( -\frac{75}{60}\text{ degrees} \rightarrow -\frac{75}{60}\times\frac{\pi}{180} \text{ radians} \)
Step 3 ：\( -\frac{75}{60}\times\frac{\pi}{180} \text{ radians} \rightarrow -\frac{5}{12}\pi \text{ radians} \)
