1. The problem statement, all variables and given/known data Consider a new vector operation, 'star' (*), defined for two dimensional vectors by A*B=(A1-B1,A2+B2). Is the resultant object a vector? 2. Relevant equations 3. The attempt at a solution I want to say that the resultant object would be a vector but I do not know how to start to go about proving it. Any help on where I should start?