Which one of the following functions provides a counterexample to the statement: if $\mathrm { f } ^ { \prime } ( x ) > 0$ for all real $x$, then $\mathrm { f } ( x ) > 0$ for all real $x$.
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Which one of the following functions provides a counterexample to the statement: if $\mathrm { f } ^ { \prime } ( x ) > 0$ for all real $x$, then $\mathrm { f } ( x ) > 0$ for all real $x$.