Mathematics II - Old Questions

18. Let v₁ = (3, 6, 2), v₂ = (-1, 0, 1), x = (3, 12, 7) and B = {v₁, v₂}. Then B is a basis for H = span {v₁, v₂}. Determine if x is in H, and if it is, find the co-ordinate vector of x relative to B.