The sign definitely can cause a lot of confusion for students. For starters,

and the list goes on.

So my focus today is to explain when to put while dealing with . First, lets recognise a few things.

: This gives us

: This gives us

Yes, the square-root can be raised to a square for the x, but notice the difference in answer in both cases. The former is a while the latter has too. This is because the square-root is always a positive square-root and does not return . On the other hand, and the which causes the .

So next time, please be alert when you introduce the .

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