正强化
参考答案:
呈现一个愉快刺激以提高一个反应发生的概率,叫正强化。
已知函数y=x2+2x+c的图象与x轴两交点的横坐标分别是x1、x2且x12+x22=c2-2c,求c值.
---How can I get to the island you mentioned?
---You can’t get there by swimming.
A.other than
B.more than
C.rather than
D.less than