How to practice concept:hilbert-spaces

Attempt a question, record the concept and assumptions, then check the available answer. Rework mistakes after revising the relevant concepts. Topic tags can overlap; review the question context.

Questions 1–10 of 11. Imported answers require independent review unless marked reviewed.

Topic practice 11 questionsPage 1 of 2

Question 54

Open question
MAMSQ2 marksNeeds review
Let

be an orthonormal set of vectors in a real Hilbert space

with inner product

. Let

, and let

be the linear span of

over

. For

, let

. Then, which of the following is/are TRUE?
Your answerSelect all correct options. You can choose more than one.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 56

Open question
MANAT2 marksNeeds review
Let

. For a sequence

, define

Consider the subspace

. Let

denote the orthogonal complement of

in the Hilbert space

. Consider

.
If the orthogonal projection of

onto

is given by

for some

, then

equals __________.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 16

Open question
MAMCQ1 markNeeds review
Let

be an orthonormal basis for a Hilbert space

. Define

and

. Then

Your answerChoose one option.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 9

Open question
MAMCQ1 markNeeds review
Let

be an orthonormal basis of a complex Hilbert space

. Consider the following statements:
P: There exists a bounded linear functional

such that

for

.
Q: There exists a bounded linear functional

such that

for

.
Then
Your answerChoose one option.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 25

Open question
MANAT1 markNeeds review
Let

be a complex Hilbert space. Let

be such that

. Then

__________.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 33

Open question
MAMCQ2 marksNeeds review
Let

be the Hilbert space of real valued square integrable functions on

equipped with the norm

. Consider the subspace

. For

, define

. Then
Your answerChoose one option.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 26

Open question
MAMCQ2 marksNeeds review
Let

be an orthonormal basis for a separable Hilbert space

with the inner product

. Define

for

. Then
Your answerChoose one option.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 47

Open question
MANAT2 marksNeeds review
Let

be the Hilbert space of all real valued square integrable functions on

with the usual inner product. Let

be the linear functional on

defined by

where

denotes the Lebesgue measure on

. Then

_________.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 48

Open question
MANAT2 marksNeeds review
Let

be an orthonormal set in a Hilbert space

and let

be such that

. Consider the set

Then the maximum possible number of elements in

is _________.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Question 39

Open question
MAMCQ2 marksNeeds review
Let

be an orthonormal basis of a Hilbert space

. Let

be given by

. For each

, define

by

. Then
Your answerChoose one option.

Log in to check the answer

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer