Consider f(x) = 8 cos5x 20 cos4x + 10 cos3x + 11 cos2x 12 cos x + 3.
i) Factor f(x) completely using rational root test.
ii) Determine zeros of f(x) on interval [0; 2).
iii) Plot zeros of f(x) you found in part (a) on the unit circle and label coordinates.
iv) Determine all zeros of f(x) State the answers in terms of z where z is integer.