### Home > INT3 > Chapter 9 > Lesson 9.1.5 > Problem9-67

9-67.

Colleen and Jolleen both use their calculators to determine $\text{sin}\left(30^\circ\right)$. Colleen gets $\text{sin}\left(30^\circ\right) = –0.9880316241$, but Jolleen gets $\text{sin}\left(30^\circ\right) = 0.5$. Is one of their calculators broken, or is something else going on? Why do they get different answers?

Try calculating $\text{sin}\left(30^\circ\right)$ in both degree mode and radian mode on your calculator.