Exercício Resolvido de Inequações
d)
\( x^{2}-3x+2\leqslant 0 \)
\[
\begin{gathered}
x^{2}-3x+2=0\\[5pt]
\Delta=b^{2}-4\mathit{ac}=(-3)^{2}-4.1.2=9-8=1\\[5pt]
x=\frac{-b\pm\sqrt{\Delta \;}}{2a}=\frac{-(-3)\pm \sqrt{1\;}}{2.1}=\frac{3\pm 1}{2}\\[5pt]
x=1\qquad \text{ou}\qquad x=2
\end{gathered}
\]
\[ \bbox[#FFCCCC,10px]
{V=\left[\;1;2\;\right]}
\]