When solving an F=ma differential equation, sometimes you want to write a as dv/dt, and sometimes you want to write it as v dv/dx. One of these generally works much better than the other.
a is dv by dt.
Is this useful? There’s no guarantee.
If it leads to, “Oh, heck!”‘s,
Take dv by dx,
And then write down its product with v.
Source: Harvard University