If the function `f: RvecA` given by `f(x)=(x^2)/(x^2+1)` is surjection, then find `Adot`

Explanation

let `f(x)=(x^2)/(x^2+1)`

Here domain is all real numbers.

Since f(x) is onto, range must
be same as codomain (A).

Thus,

`f(x)=1−(1)/(x^2+1)`

Now `x^2+1≥1`

`⇒0<1/(x^2+1)≤1`

`⇒−1≤-1/(x^2+1)<0`

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