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Graph sketching

When dealing with squares and roots how would I avoid the extraneous solutions? Should I always consider the domain of the function before manipulating it?7E388C3F-CB27-4E4A-883E-2AA2C31A5FD5.jpeg
(edited 2 years ago)
Reply 1
Yes, the domain is x>=0 here so obviously any "solutions" with x<0 don't satisfy the original function.

A squaring step like this isn't generally an "if and only if" so you'd have to interpret the solutions found.
(edited 2 years ago)

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