[tex]a).x^2-2x-3 \geq 0 \\ (x-3)(x+1) \geq 0 \\ x-3 \geq 0 \\ x \geq 0+3 \\ x \geq 3 \\ x+1 \geq 0 \\ x \geq 0-1 \\ x \leq -1[/tex]
[tex]b).x^2-36\ \textless \ 0 \\ (x-6)(x+6)\ \textless \ 0 \\ x-6\ \textless \ 0 \\ x\ \textless \ 0+6 \\ x\ \textless \ 6 \\ x+6\ \textless \ 0 \\ x\ \textless \ 0-6 \\ x\ \textgreater \ -6[/tex]
