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Question 5 Consider the following matrix over R: A = (a) [3 Marks] Show that A is orthogonal. (b) [6 Marks] Let P2(R) denote the vector space of all polynomials of degree two or less over the field of real numbers. Consider the following inner product on P2 (R) (P. q) = cobo + ab, + (2bz, where p(x) = do + air + a2-, q(x) = bo + bir + bar. Show that S = {1,r,x } forms an orthonormal basis of P2(R) with respect to the above inner product