1. ## calculus

but in the answer they told that y^2=x-1 is not a function.there are several example in other books like this one.according to the other book it is not a function

2. Originally Posted by Mohsin
but in the answer they told that y^2=x-1 is not a function.there are several example in other books like this one.according to the other book it is not a function
You've already been asked to continue this conversation in the original thread. It is too confusing to post new information without the original.

If you are having trouble finding the original post, simply ask.

-Dan

3. Originally Posted by Mohsin
but in the answer they told that y^2=x-1 is not a function.there are several example in other books like this one.according to the other book it is not a function

y^2 = x -1
"is not a function" if you mean y as a function of x.
It is the square of y, where y is a function of x.

y = f(x) = sqrt[x-1] ------the positive root of the square root only.
If you include the negative root, then y is not f(x) anymore. Because y will have two values for every x-value in the domain.