- #1
Newtons Apple
- 57
- 1
hey guys. Something's been bothering me.. Well two things..
First of all, when looking at an algebraic equation and testing to see if its a function, why can X be squared, but not Y? our professor and book, gives the impression that something like:
x^2 +y =1 is a function
while..
-x +y^2 = 1 is NOT a function
Why is this? I know that in a function, the domain can't be linked to two or more elements in the range.. is that what the second equation is saying? Is the x and y in these equations representations of the domain and range of a function?
My 2nd main question is, what is the difference in saying
f(x) = 1-x^2 and saying y = 1-x^2?
Are they both the same thing? Why does y = f(x) anyway? I thought that f(x) was just the name of the function being presented, but then I saw my professor draw a graph, with the 'Y' letter on the yaxis replaced by the f(x) notation and was severely confused!
First of all, when looking at an algebraic equation and testing to see if its a function, why can X be squared, but not Y? our professor and book, gives the impression that something like:
x^2 +y =1 is a function
while..
-x +y^2 = 1 is NOT a function
Why is this? I know that in a function, the domain can't be linked to two or more elements in the range.. is that what the second equation is saying? Is the x and y in these equations representations of the domain and range of a function?
My 2nd main question is, what is the difference in saying
f(x) = 1-x^2 and saying y = 1-x^2?
Are they both the same thing? Why does y = f(x) anyway? I thought that f(x) was just the name of the function being presented, but then I saw my professor draw a graph, with the 'Y' letter on the yaxis replaced by the f(x) notation and was severely confused!