Quiz 12: Eigenvalues and modelling
Question 1
The matrix has
eigenvalues ,
with corresponding
eigenvectors
and .
Which of the following matrices and satisfy the equation ?
Which of the following matrices and satisfy the equation ?
Not correct. Choice (a)
is false.
Not correct. Choice (b)
is false.
Not correct. Choice (c)
is false.
Your answer is correct.
For these two matrices .
In fact
and .
Question 2
The matrix has
eigenvalues ,
,
with corresponding
eigenvectors ,
and
.
Which of the following matrices and are such that ?
Which of the following matrices and are such that ?
Not correct. Choice (a)
is false.
Not correct. Choice (b)
is false.
Your answer is correct.
Not correct. Choice (d)
is false.
.
Question 3
Which are the matrices
and such
that
when
?
Not correct. Choice (a)
is false.
Your answer is correct.
The eigenvalues of
are ,
and the corresponding
eigenvectors are
and .
Hence
and .
Not correct. Choice (c)
is false.
Not correct. Choice (d)
is false.
Question 4
The matrix has
eigenvectors ,
and
.
Which are the matrices and such that ?
Which are the matrices and such that ?
Your answer is correct.
,
,
, .
, .
Not correct. Choice (b)
is false.
Not correct. Choice (c)
is false.
Not correct. Choice (d)
is false.
Question 5
Consider the matrix .
Find a matrix
such that for some
diagonal matrix .
Not correct. Choice (a)
is false.
It is true that
where ,
but det ,
so
does not exist.
Not correct. Choice (b)
is false.
Not correct. Choice (c)
is false.
Your answer is correct.
Note that
and are
such that ,
but det ,
so
does not exist.
Question 6
Let the Leslie matrix for a female population divided into 4 equal age groups
be
What is the fraction of the second age group which survives to the next generation
?
Not correct. Choice (a)
is false.
Your answer is correct.
Not correct. Choice (c)
is false.
Not correct. Choice (d)
is false.
Question 7
Let the Leslie matrix for a female population divided into 4 equal age groups
be
What is the average number of female offspring for the 2nd age group ?
Not correct. Choice (a)
is false.
Not correct. Choice (b)
is false.
Not correct. Choice (c)
is false.
Your answer is correct.
Question 8
We are given that a female population is divided into 3 equal age groups and that the
average no. of female offspring for the first, second and third age groups are
14.5
and 3.2 respectively. If the proportion of the first and second age groups which
survive to the next age group is 0.9 and 0.7 respectively, what is the Leslie matrix
which models this behaviour ?
Not correct. Choice (a)
is false.
Not correct. Choice (b)
is false.
Your answer is correct.
Not correct. Choice (d)
is false.
Question 9
The female population of lemmings is divided into 4 equal age groups which are
described by the following statisics:
What is the Leslie matrix which models this behaviour ?
Not correct. Choice (a)
is false.
Your answer is correct.
Not correct. Choice (c)
is false.
Not correct. Choice (d)
is false.
Question 10
Two countries, A and B, have open door immigration policies between them. Let the population
of countries
and at the
end of year
be and
respectively.
The population of country A grows by 2% per year, excluding migration and the population
of country
grows by 5% per year excluding migration. It is observed that 10% of the
increased population of country A migrates to country B and 7% of the
increased population of country B migrates to country A each year. If
, what is
the matrix
?
Not correct. Choice (a)
is false.
Not correct. Choice (b)
is false.
Your answer is correct.
Not correct. Choice (d)
is false.










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