Answer:
See explanation
Step-by-step explanation:
The range of the cosine function is [tex]-1\le \cos x\le 1[/tex]
Therefore [tex]arc \cos (-2\sqrt{2})[/tex] is not defined.
Assuming your question is rather [tex]arc \cos (-\frac{\sqrt{2}}{2})[/tex]
Then [tex]arc \cos (-\frac{\sqrt{2}}{2})=\pi-arc \cos (\frac{\sqrt{2}}{2})[/tex] in the second quadrant.
[tex]arc \cos (-\frac{\sqrt{2}}{2})=\pi-\frac{\pi}{4}[/tex]
[tex]arc \cos (-\frac{\sqrt{2}}{2})=\frac{3\pi}{4}[/tex]
