If V = U ⊕ U⟂ and V = W ⊕ W⟂, and if
S1: U → W and S2: U⟂ →
W⟂ are isometries, then the linear operator defined for
u1 ∈ U and u2 ∈ U⟂ by the formula
S(u1 + u2) = S1u1 +
S2u2 is a well-defined linear isometry. Prove
this.
Let W denote the set of English words. For u,
v ∈ W, declare u ∼ v provided
that u, v have the same length and u,
v have the same first letter and u, v
have the same last letter.
a) Prove that ∼ is an equivalence relation.
b) List all elements of the equivalence class [a]
c) List all elements of [ox]
d) List all elements of [are]
e) List all elements of [five]. Can you find more...
True/False Question: If sppan{u,v}=W where u not equal to v.
Then dim(W)=2.
Answer: False
Reasoning let u=1, v=2 then span(1,2}=R but dim(R)=1 not 2.
I know the answer is false. please tell me whether my reasoning
is correct.
Let A ∈ L(U, V ) and B ∈ L(V, W). Assume that V is
finite-dimensional.
Let X be a 3 × 5 matrix and Y be a 5 × 2 matrix. What are the
largest and smallest possible ranks of X, Y, and XY? Give examples
of the matrix to support your answers
3.5.4 ([Ber14, Ex. 3.6.14]). Let T : V → W and S : W → U be
linear maps, with V finite dimensional.
(a) If S is injective, then Ker ST = Ker T and rank(ST) =
rank(T).
(b) If T is surjective, then Im ST = Im S and null(ST) − null(S)
= dim V − dim W
Let X ∈ L(U, V ) and Y ∈ L(V, W). You may assume that V is
finite-dimensional.
1)Prove that dim(range Y) ≤ min(dim V, dim W). Explain the
corresponding result for matrices in terms of rank
2) If dim(range Y) = dim V, what can you conclude of Y? Give
some explanation
3) If dim(range Y) = dim W, what can you conclude of Y? Give
some explanation
1. Let U = {r, s, t,
u, v, w, x, y,
z}, D = {s, t, u,
v, w}, E = {v, w,
x}, and F = {t, u}. Use roster
notation to list the elements of D ∩ E.
a.
{v, w}
b.
{r, s, t, u, v,
w, x, y, z}
c.
{s, t, u}
d.
{s, t, u, v, w,
x, y, z}
2. Let U = {r, s,
t, u, v, w, x,
y, z},...