Therefore the acceleration since I call - that the "plus x direction"-- that was my plus sign-- must come out plus.

因此加速度必然,是在x正方向-,这里是正好，必然如此。

youdao

Therefore the acceleration since I call - that the "plus x direction"-- that was my plus sign-- must come out plus.

因此加速度必然,是在x正方向-,这里是正好，必然如此。

youdao