Question

Why is the square root function y=srtx only positive for y?

Answer 1

Why indeed :3
\[\Large y = \sqrt{x}\]

Answer 2

After all, if you want a number, which, when squared, say, gives 16, you can get either 4 or -4 right?

Answer 3

Yes hahaha

Answer 4

It all goes back to the definition of a function :)

Answer 5

\[\huge \color{blue}y = f(\color{red}x)\]

Answer 6

Remember that for every x that you plug into a function, there MUST be only ONE value of y that comes out...

x are 'inputs', y are 'outputs' and for every input, there must be EXACTLY one output for it to be a function :)

Answer 7

So as for\[\Large \color{blue}y = \sqrt{\color{red}x}\] well, it won't BE a function if we allow y to take negative as well as positive values. Hence only positive ^_^

Answer 8

:) thankss mann. Lots of help

Answer 9

vertical line test