Answer:
[tex]\cot 225\degree=1[/tex]
Step-by-step explanation:
We want to use the unit circle to find the value of [tex]\cot 225\degree[/tex].
Note that [tex]225\degree[/tex] is in the third quadrant.
This makes an angle of [tex]45\degree[/tex] with the positive x-axis.
[tex]\cot 225\degree=\frac{\cos225\degree}{\sin225\degree}[/tex]
[tex]\cot 225\degree=\frac{-\cos45\degree}{-\sin45\degree}[/tex]
On the unit circle;
[tex]\cos 45\degree=\sin 45\degree=\frac{\sqrt{2} }{2}[/tex]
[tex]\cot 225\degree=\frac{-\frac{\sqrt{2}}{2}}{-\frac{\sqrt{2}}{2}}[/tex]
[tex]\cot 225\degree=1[/tex]
