Part I: True or false questions.
For each of the following questions, state whether it is true or false. Justify your answer.
1. The map T : IR3 -+ IR2, defined by T(x,y,z) = (x + y +2, y + z) is not a linear transfor-
mation.
(3)
2. If A and B are similar matrices then there exists an invertible matrix P such that AP =
BP.
(3)
3. For an n x n matrix A, the geometric multiplicity of each eigenvalue of A is less than or
equal to the algebraic multiplicity.
(3)
4. The index and signature of the quadratic form
q(x,y, z) = 3x2 - 4xy + 6y 2 + 4yz - 7z2 are respectively 3 and 2.
(3)
5. If q is a quadratic form on a vector space V, then q(-0:) = -q(0:).
(3)
Part II: Work out problems.
1. Let V and Vv be vector spaces over a field K and let T: V -+ W be a mapping. State
what it means to say T is linear transformation.
(3)
2. Let T be the mapping T: P3 -+ P2 defined by T(a 0 + a1x + a2x2 + a3x 3 ) = 2a 1 - a2x 3 .
Then
(a) show that T is linear.
(12)
(b) find a basis for the kernel of T.
(7)
3. Let V be the vector space of functions with basis S = {sin 2t, cos 2t, e- 3l} and let
D: V -+ V be the differential operator defined by D f(t) = ftf(t). Find the matrix
representing D in the basis S.
(8)
4. Let A and B be n x n similar matrices.Then prove that A and B have the same deter-
minant.
(6)
5. Consider the bases B = {(1,0,0),(0,1,0),(0,0,1)}
of IR3.
and C = {(1,0,1),(0,1,1),(1,1,0)}
(a) Find the change of basis matrix Pc.-6 from B to C.
(10)
(b) Use the result in (a) and to compute [v]c where v = (1, 3, 5).
(5)
0
G D 6. (a) Show that >.=. 4 is an eigenvalue of the matrix A=
2
and find an eigen-
0
vector corresponding to this eigenvalue.
(17)
0
G (b) Show that v - ( 1) is an eigenvector for the matrix A -
1 ~2) and find
0
the corresponding eigenvalue of A.
(6)