Random math X

Express the equation ${2x^2}+4x-1$

In the form $a{(x+b)^2}+c$

Where $\{a,b,c\}\in\mathbb{Z}$

$\begin{array}{|rcll|} \hline && 2x^2+4x-1 \\ &=& 2\cdot (x^2+2x) - 1 \\ &=& 2\cdot \Big( (x+1)^2 -1 \Big) - 1 \\ &=& 2\cdot (x+1)^2 -2 - 1 \\ &=& 2\cdot (x+1)^2 -3 \\ \hline \end{array}$