I. .l (c) Use Givens rotations to transform the vector to a multiple of the first unit vector. Specify the Givens rotations you used. 4. [1+2+1pt] Let the matrix A 6 RM\" be defined by its components a,\" = 22' for 75 = 1, ...n, ai,i+1 = 7:, ch...\" = i for Z: 1, ...n 1, the remaining components are zero. (a) Sketch the Gerschgorin discs of A. (b) Use Gerschgorin's Theorem and facts about symmetric matrices to show that all eigenvalues of A are real numbers, larger or equal 1. (c) Using Gerschgorin discs, find an upper bound for the eigenvalues of A