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such that
. Let
, where
is the identity matrix. Which of the following is true?
is Hermitian and unitary.
is Hermitian but not unitary.
is unitary but not Hermitian.
is neither Hermitian nor unitary.
is a
matrix with eigenvalues
and
, what is det
? Note: det denotes the determinant.



be a Hermitian matrix. Which of the following options is correct for the values of
and
?



. Find the condition on
and
for which the matrix
is positive-definite.
and 

and 
and 
around
?



is a real matrix of shape
, which of the following is/are true?
is a positive semi-definite matrix.
is a positive semi-definite matrix.
is positive semi-definite if and only if
is a symmetric matrix.
is positive semi-definite if and only if
is a square matrix.
:
Which of the following options is/are correct?
is unitary for all real values of
other than
.
is unitary for
.
is unitary for
.
, then all eigenvalues of
satisfy
.
is any non-zero real value, then all eigenvalues of
satisfy
.
whose graph is shown below.
and
correspond to local minima of
.
We run two separate instances of gradient descent with the same learning
but different initial points. (1) Starting from the point
(2) Starting from the point
Assume that
and
are very small positive quantities. Which of the following is/are true if we run gradient descent for a large number of iterations?



, but will diverge to negative infinity
, but will diverge to infinity
is a real matrix of shape
with the following singular values:
. Find the rank of
.
. Find the sum of all the singular values of
.
is minimized using the gradient descent algorithm. Let
denote the value of
at which
is minimized.Starting from the initial point
, one iteration of gradient descent is performed with a learning rate of
. If
denotes the point obtained after this iteration, find the value of
. Enter the answer correct to one decimal place.
Run PCA on this dataset. Based on the above data, answer the given subquestions.
is the covariance matrix of the dataset, find
. Enter the nearest integer as your answer.
be the unit-norm eigenvector corresponding to the smallest eigenvalue of the covariance matrix. Find the variance of the dataset along the direction
. Enter the nearest integer as your answer.