[tex]\bf \qquad \qquad\textit{discriminant of a quadratic} \\\\\\ \stackrel{\stackrel{a}{\downarrow }}{2}x^2\stackrel{\stackrel{b}{\downarrow }}{+4}x\stackrel{\stackrel{c}{\downarrow }}{-2} ~~~~~~~~ \stackrel{discriminant}{b^2-4ac}~\hspace{3em}\implies 4^2-4(2)(-2)\implies 16+16 \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ ~\hfill 32~\hfill[/tex]
