If you call this plus, then if you get a minus sign, you know that the velocity is in the opposite direction.

你若称此为正号，你若想要一个负号，你们知道的，相反方向的速度。

youdao

If you call this plus, then if you get a minus sign, you know that the velocity is in the opposite direction.

你若称此为正号，你若想要一个负号，你们知道的，相反方向的速度。

youdao