v1=1, v=2=-1, m1=7

It looks like you're dealing with a problem that involves variables and possibly equations. However, the notation you've provided is a bit unclear.

Could you clarify what you mean by "v1=1, v=2=-1, m1=7"? Are you trying to solve equations or perform a calculation? If you provide more context or details on what you're trying to accomplish, I can help you better!