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How do you decide whether the relation #sqrt(x+40)# defines a function?

Answer 1

A "function" is any description of related values.

A "function" is any description of related values. The expression given is missing the implied "is equal to..." e.g. #y = sqrt(x + 40)#, but it may be considered a "function" just as well. If defines a relationship of values, of which one is variable.

Its continuity over all real numbers may or may not exist, but that does not indicate if it is a function.

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Answer 2

Hazel Anglin

To determine if the relation ( \sqrt{x + 40} ) defines a function, we check if each input (x-value) corresponds to exactly one output (y-value). If every x-value results in a unique y-value, then the relation defines a function.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.