g 4. For vectors a = h2, 3, 4i, b = h−3, 1, 0i, c = h1, 1, 1i ∈ R 3 , verify the following properties of the cross product (a) a × (b × c) = (a · c)b − (a · b)c (b) a × (b × c) + b × (c × a) + c × (a × b) = 0