Precalculus Examples

\sin (- 225)

$\sin (- 225)$

Step 1

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

\sin (45)

$\sin (45)$

Step 2

The exact value of

\sin (45)

$\sin (45)$ is

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

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

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

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

Step 3

The result can be shown in multiple forms.

Exact Form:

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

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

Decimal Form:

0.70710678 \dots

$0.70710678 \dots$