Let T be a linear operator on a finite-dimensional complex
vector space V . Prove that T is diagonalizable if and only if for
every λ ∈ C, we have N(T − λIV ) = N((T − λIV
)2).
suppose that T : V → V is a linear map on a finite-dimensional
vector space V such that dim range T = dim range T2. Show that V =
range T ⊕null T. (Hint: Show that null T = null T2, null T ∩ range
T = {0}, and apply the fundamental theorem of linear maps.)
Let V be a finite-dimensional vector space over C and T in L(V).
Prove that the set of zeros of the minimal polynomial of T is
exactly the same as the set of the eigenvalues of T.
Let T be an operator on a finite-dimensional complex vector
space V, and suppose that dim Null T = 3, dimNullT2 =6. Prove that
T does not have a square root; i.e. there does not exist any S ∈ L
(V) such that S2 = T.
6. Let V be the vector space above. Consider the maps T : V → V
And S : V → V
defined by T(a1,a2,a3,...) = (a2,a3,a4,...) and S(a1,a2,a3,...)
= (0,a1,a2,...).
(a) [optional] Show that T and S are linear.
(b) Show that T is surjective but not injective.
(c) Show that S is injective but not surjective.
(d) Show that V = im(T) + ker(T) but im(T) ∩ ker(T) ̸= {0}.
(e) Show that im(S) ∩ ker(S) = {0}...
Let V be a finite dimensional vector space over R. If S is a set
of elements in V such that Span(S) = V ,
what is the relationship between S and the basis of V ?
V and W are finite dimensional inner product spaces,T: V→W is a
linear map
1A: Give an example of a map T from R2 to itself (with the usual
inner product) such that〈Tv,v〉= 0 for every map.
1B: Suppose that V is a complex space. Show
that〈Tu,w〉=(1/4)(〈T(u+w),u+w〉−〈T(u−w),u−w〉)+(1/4)i(〈T(u+iw),u+iw〉−〈T(u−iw),u−iw〉
1C: Suppose T is a linear operator on a complex space such
that〈Tv,v〉= 0 for all v. Show that T= 0 (i.e. that Tv=0 for all
v).
Let ? and W be finite dimensional vector spaces and let ?:?→? be
a linear transformation. We say a linear transformation ?:?→? is a
left inverse of ? if ST=I_v, where ?_v denotes the
identity transformation on ?. We say a linear transformation ?:?→?
is a right inverse of ? if ??=?_w, where ?_w
denotes the identity transformation on ?. Finally, we say a linear
transformation ?:?→? is an inverse of ? if it is
both a left and right...
Suppose V is finite-dimensional and S, T are operators on V .
Prove that ST is bijective if and only if S and T are both
bijective.
Note: Don’t forget that bijective maps are precisely those that
have an inverse!
1. Let V be real vector space (possibly infinite-dimensional),
S, T ∈ L(V ), and S be in- vertible. Prove λ ∈ C is an eigenvalue
of T if and only if λ is an eigenvalue of STS−1. Give a description
of the set of eigenvectors of STS−1 associated to an eigenvalue λ
in terms of the eigenvectors of T associated to λ.
Show that there exist square matrices A, B that have the same
eigenvalues, but aren’t similar. Hint:...