Need help with questions 9-14 please

' (9)Let 214 A: '021 \"523 (a) Solve for $2 in the system Ax : b where bT 2 [1 2 3] using Cramer's Rule. Verify your answer by using A\". (b) Express A and A'1 as a product of elementary matrices. You have to write out all the elementary matrices. (10) Let 1 0 2 2 1 0 3 2 1 Find adj(A) (Do this in two ways: The long way, i.e., by the denition of the adjoint, and the shorter way via the relationship between the adjoint and the inverse) (11) Let 2 = 1 + 2i,w : 2 + 31'. Find 22w, 1112,1172, 32/111, Izwl. (12) Express 2 (given in (11)) in polar form, and from this calculate 2'4, and the square roots of 2; 21/2. Sketch 2,24, 21/2 together on the complex plane and identify their moduli and principle arguments. (13) Find the formula in rectangular form (i.e., c+id) of z\" where z is given in rectangular form z : a+ib. Do this by solving a system of equations for the two unknowns c, d, and determine these equations by noting that (c+ id)(a + ib) = 1. 6 (14) Find all the roots of 411:3 + 5x2 5x + 2