# Recent questions tagged p11

### Show that the Modulus Function $f : R \to R$, given by $f(x) = |\;x\;|$, is neither one-one nor onto, where$|\;x\;|\; is\; x$, if $x$ is positive or $0$ and $|\;x\;|\; is\;$ $-$$x$, if $x$ is negative.

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