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Intro to functions

Is f(x) = (1-x^2)^-1 a total function? If it isnt, what is its domain?
Ty for all the help
Original post by phillipJFries
Is f(x) = (1-x^2)^-1 a total function? If it isnt, what is its domain?
Ty for all the help


Look at the definition of what it means for ff to be a total function.

Is (1x2)1(1-x^2)^{-1} defined for all xRx \in \mathbb{R}?
Ahh the graph has asymptotes at 1 and -1, so it is not.
Therefore the domain is x>1, x<-1, -1>x<1 i assume? Is this the correct notation?
(edited 6 years ago)
Original post by phillipJFries
Ahh the graph has asymptotes at 1 and -1, so it is not.
Therefore the domain is x>1, x<-1, -1>x<1 i assume? Is this the correct notation?


Not sure how 1>x<1-1>x<1 in this situation since that just means x<1x<-1, thus no new info.

The correct notation would be to say xR{1,1}x \in \mathbb{R} \setminus \{ -1, 1 \}

Or (,1)(1,1)(1,)(-\infty, -1) \cup (-1, 1) \cup (1, \infty)

Or x<1x<-1, 1<x<1-1<x<1, x>1x>1
(edited 6 years ago)

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