Table 3.

Descartes Rule of Signs applied to the second degree polynomial R(q)

Case	$a_2$	$b_2$	$c_2$	$d_2$	Real positive	Real negative	Complex
1	+	+	+	+	0	3/1	0/2
2	+	+	–	+	2/0	1	0/2
3	+	–	+	+	2/0	1	0/2
4	+	–	–	+	2/0	1	0/2