Question
Let $f:R \to R$ be defined by
$$$f\left( x \right) = \left\{ {\matrix{
{k - 2x,\,\,if} & {x \le - 1} \cr
{2x + 3,\,\,if} & {x > - 1} \cr
} } \right.$$$
If $f$has a local minimum at $x=-1$, then a possible value of $k$ is