Length and Dot Product in R". Suppose u and v are unit vectors in R. Prove ||ū - V || = √₂√1 - u [5pts.] Orthonormal Bases. Suppose U = {ū₁,…, un} is an orthonormal basis for R" and x ER". Prove if x u₁ = R¹ || u; || for all i, 1 ≤ i ≤n, then X = ₁ + + Un =