Trigonometry Examples

$\sin (180 - 45)$

Step 1

Subtract $45$ from $180$ .

$\sin (135)$

Step 2

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

$\sin (45)$

Step 3

The exact value of $\sin (45)$ is $\frac{\sqrt{2}}{2}$ .

$\frac{\sqrt{2}}{2}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$\frac{\sqrt{2}}{2}$

Decimal Form:

$0.70710678 \dots$