Precalculus Examples

$\sin (405^{+})$

Step 1

Since $405^{+}$ is not an angle where the values of the six trigonometric functions are known, try using the sum or difference formula.

$405^{+}$ is not an exact angle

Step 2

First, split the angle into two angles where the values of the six trigonometric functions are known. In this case, $405^{+}$ can be split into $60$ .

$\sin (60)$

Step 3

The exact value of $\sin (60)$ is $\frac{\sqrt{3}}{2}$ .

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

Step 4

The result can be shown in multiple forms.

Exact Form:

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

Decimal Form:

$0.86602540 \dots$