The unit circle (radius is one unit) for the trigonometric function is,
The coordinate of point P is,
[tex]P(\frac{\sqrt[]{2}}{2},-\frac{\sqrt[]{2}}{2})[/tex]
So value of tan 315 is,
[tex]\begin{gathered} \tan 315=\frac{-\frac{\sqrt[]{2}}{2}}{\frac{\sqrt[]{2}}{2}} \\ =-1 \end{gathered}[/tex]
Answer: -1
