Lets say you have 3 vectors v1, v2,v3. They form a 3x3 matrix. Let's say you're asked if v3 is a linear combo of the other two vectors. Rref of the matrix gives 1 0 1 0 1 0 0 0 0 The definition of a Linear combo is v3=c1v1+c2v2 where c1 and c2 are scalars. Okay do this is where I get con fused . If u look at the above matrix c2=0 which means v3=c1v1. Would that mean its not a linear combination of v2 since c2=0? Also is 0 a scalar?