Rule 1 was not satisfied in this example, in that the roots of the denominator are 0 + j 3 {\displaystyle 0+j3} and 0 − j 3 {\displaystyle 0-j3} .
这个例子不满足规则1，因为分母为零的根为 0 + j 3 {\displaystyle 0+j3} 和 0 − j 3 {\displaystyle 0-j3} 。