Precalculus Examples

$\cos (\frac{π}{6}) + \sin (\frac{5 π}{6})$

Step 1

The exact value of $\cos (\frac{π}{6})$ is $\frac{\sqrt{3}}{2}$ .

$\frac{\sqrt{3}}{2} + \sin (\frac{5 π}{6})$

Step 2

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant.

$\frac{\sqrt{3}}{2} + \sin (\frac{π}{6})$

Step 3

The exact value of $\sin (\frac{π}{6})$ is $\frac{1}{2}$ .

$\frac{\sqrt{3}}{2} + \frac{1}{2}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$\frac{\sqrt{3}}{2} + \frac{1}{2}$

Decimal Form:

$1.36602540 \dots$