Precalculus Examples

$\tan (120)$

Step 1

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because tangent is negative in the second quadrant.

$- \tan (60)$

Step 2

The exact value of $\tan (60)$ is $\sqrt{3}$ .

$- \sqrt{3}$

Step 3

The result can be shown in multiple forms.

Exact Form:

$- \sqrt{3}$

Decimal Form:

$- 1.73205080 \dots$