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**IloveIl** **When do the inverse trigonometric functions cancel each other? I mean that while sin(arcsin(2/3))=2/3, you can't just do that here: arcsin(sin(5π/13)). when do they cancel each other and when you need to be careful? Thanks.**

**In my homework I have examples that show that sin(arcsin(2/3))=2/3. So it is clear that the functions cancel each other. But in another example: arcsin(sin(5π/13π). Here, it shows a little work before they cancel what sin does: arcsin(sin(5π/13)=arcsin(sin(π−5π/13))=2π/7.**