## Values of Trigonometric Functions

Principal values of the trigonometric functions between 0 ° and 90 ° are:
 sine cosine tangent 0 ° 0 1 0 30 ° $\frac{1}{2}$ $\frac{\sqrt{3}}{2}$ $\frac{1}{\sqrt{3}}$ 45 ° $\frac{1}{\sqrt{2}}$ $\frac{1}{\sqrt{2}}$ 1 60 ° $\frac{\sqrt{3}}{2}$ $\frac{1}{2}$ $\sqrt{3}$ 90 ° 1 0 Not Defined
Suppose we want to find the exact value of 12cos30°-2tan60°. We consult the table.
$12cos30°-2tan60°=12 \times \frac{\sqrt{3}}{2} - 2 \times \sqrt{3} = 6 \sqrt{3}-2 \sqrt{3}=4 \sqrt{3}$