
Reading a function
okay, so i need to determine whether or not f is onetoone and onto. if so, find f^1.
im pretty sure i can do it, i just dont know how to read the thing.
A=R \ {0} and B=R \ {2} and f: A>B
f(x)= 1/x + 2
where R is the reals. can anyone please explain to me how to read that?

$\displaystyle f:A\to B$ is bijective if and only if $\displaystyle \forall y\in B$, the equation $\displaystyle f(x)=y$ has an unique solution $\displaystyle x\in A$
Now, let $\displaystyle y\in\mathbf{R}\{2\}$
$\displaystyle \displaystyle f(x)=y\Leftrightarrow \frac{1}{x}+2=y\Leftrightarrow \frac{1}{x}=y2\Leftrightarrow x=\frac{1}{y2}\in\mathbf{R}\{0\}$