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# Why do we call things like this a function

Why do we call $$f(x) = \sqrt x$$ a function, if by definition $$y = \sqrt x$$ is not a function since for included values of $$x$$, it gives us more than one value of $$y$$ considering the positive and negative answers in the radicals?

Note by Geneveve Tudence
1 year, 4 months ago

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Whenever we are calling it function domain is R+ and range too

- 1 year, 4 months ago

Have you read the list of common misconceptions wiki ? I recommend reading #8 in the "Powers and Square Roots" section of that wiki.

- 1 year, 4 months ago

Note that if you are using the radical "symbol" then you are talking only about the positive root.
So, $$\sqrt{64} = 8$$ and not $$\pm8$$.

- 1 year, 4 months ago