PARCC Algebra II Trigonometric Functions. Practice it free.

$\dfrac{\pi}{2} \times \dfrac{180°}{\pi} = 90°$.

$\tan 45^{\circ} = 1$ and $45^{\circ}$ lies in arctangent's principal range, so $\arctan(1) = 45^{\circ}$.

$\tan\theta = \dfrac{\sin\theta}{\cos\theta} = \dfrac{-5/13}{12/13} = -\dfrac{5}{12}\textsf{.}$

The angle $\dfrac{5\pi}{6}$ is in Quadrant II with reference angle $\dfrac{\pi}{6}$. Sine is positive there, so $\sin\left(\dfrac{5\pi}{6}\right) = \sin\left(\dfrac{\pi}{6}\right) = \dfrac{1}{2}$.

$\dfrac{2\pi}{3} \times \dfrac{180°}{\pi} = 120°$.

The domain of $\arcsin(x)$ is $[-1,\, 1]$.

$\sec\theta = \dfrac{1}{\cos\theta} = \dfrac{1}{-4/7} = -\dfrac{7}{4}\textsf{.}$

On the unit circle, $\cos\left(\dfrac{\pi}{3}\right) = \dfrac{1}{2}$.