VII. FACTORISATION OVER C-, R- AND J-FIELDS
Use the factor theorem to show (1-4) that:
1.
is a factor of ![]()
2.
is a factor of ![]()
3.
is a factor of ![]()
4.
is a factor of ![]()
5. Given that
, find the value of a if 
6. Given that
, find the value of a if
.
7. Given that
, find the values of a and b if i and
are zeros of P(x).
8. Given that
, find the values of a and b if P(2)=0 and P(1-i)=0.
Complete factorise the following (9-24):
9.
over C
10.
over C
11.
over (i) J (ii) C
12.
over C.
13.
over C.
14.
over (i) J and (ii) C.
15.
over (i) Q (ii) R (iii) C.
16.
over (i) R (ii) C
17.
over (i) R (ii) C.
18.
over C.
19.
over (i) R (ii) C.
20.
over (i) R (ii) C.
21.
over (i) R (ii) C given that
is one linear factor.
22.
over C.
23.
over (i) R (ii) C.
24.
over C.
Find z in (25-31);
25. ![]()
26.
if (i)
(ii) ![]()
27. ![]()
28. ![]()
29. ![]()
30. ![]()
31. ![]()
32. Find the values of the real numbers a and b , such that 1+i is a root of the equation ![]()
Find z in 33-39:
33. ![]()
34. ![]()
35. ![]()
36. ![]()
37. ![]()
38. ![]()
39. ![]()
Write down an equation of the lowest possible degree with (i) complex coefficients, (ii) rational coefficients and having the following among its roots:
40.
41.
42.
, ![]()
43.
of multiplicity 2.
44.
45. ![]()
Find and ploton the complex plane (46-55):
46. The square root of
47. The square root of ![]()
48.
49. ![]()
50.
51. The cube root of 64.
52. The fourth root of 8. 53. The sixth root of -1
54. The sixth root of 64. 55. The cube root of -8.
56. Find real values of a for which ai is a solution of the polynomial equation ![]()
57. Find the values which the real numbers a and b must take for z=1 to be a root of the complex equation ![]()
58. If 1,
, and
are the cube roots of unity, prove that (i)
, (ii)
and (iii)
.
59. If
, prove that
(i) ![]()
(ii) ![]()
![]()
Show that the roots of
are the four complex roots of
. Deduce that ![]()
60. Find (a) the three roots of the equation ![]()
(b) the remainder when
is divided by ![]()
61. Find the real numbers k such that
is a root of the equation
. Hence or otherwise find the three roots of the equation.
62. Solve the following equations using a calculus method.
(a)
given that it has a root of multiplicity 2.
(b)
given that it has a root of multiplicity 3.