All Linear Algebra Resources
Example Questions
Example Question #51 : Operations And Properties
Let , , and be real numbers such that
, ,
and the determinant of is 8.
True or false: The determinant of is 8.
False
True
True
is the transpose of - the matrix formed by interchanging the rows of with its columns. The determinant of a matrix and that of its transpose are equal, so, since has determinant 8, so does .
Example Question #51 : Operations And Properties
Find .
, the conjugate transpose of , is the result of transposing the matrix - interchanging rows with columns - and changing each entry to its complex conjugate. First, find transpose :
,
so
Change each entry to its complex conjugate:
.
Example Question #53 : Operations And Properties
Find .
None of the other choices gives the correct response.
, the transpose, is the result of switching the rows of with the columns.
,
so
.
Example Question #31 : The Transpose
and are skew-symmetric matrices.
Which of the following is true of ?
By definition, the transpose of a skew-symmetric matrix is equal to its additive inverse . It follows that
Example Question #55 : Operations And Properties
Find .
, the conjugate transpose of , is the result of transposing the matrix - interchanging rows with columns - and changing each entry to its complex conjugate. First, find transpose :
,
so
Change each entry to its complex conjugate:
Example Question #56 : Operations And Properties
Which of the following is equal to ?
None of the other responses gives the correct answer.
, the conjugate transpose of , is the result of transposing the matrix - interchanging rows with columns - and changing each entry to its complex conjugate. First, find transpose :
Each entry of is equal to the complex conjugate of the corresponding entry of . However, each entry in is real, so each entry is equal to its own complex conjugate, and
Example Question #56 : Operations And Properties
Find .
None of the other choices gives the correct response.
, the transpose, is the result of switching the rows of with the columns.
,
so
.
Example Question #38 : The Transpose
Which of the following is equal to ?
is the transpose of - the result of interchanging the rows of with its columns. is the conjugate transpose of - the result of changing each entry of to its complex conjugate. Therefore, if
,
we can find by simply changing each entry in to its complex conjugate:
Example Question #32 : The Transpose
True or false: is an upper triangular matrix.
False
True
True
is the result of interchanging rows of with columns, then changing each entry to its complex conjugate. Also, is equal to , so perform the same process on :
A matrix is upper triangular if all elements below its main (upper-left corner to lower right corner) diagonal are equal to 0. These elements in are displayed in red above. Since all of the lower-triangular elements of are zeroes, is upper triangular.
Example Question #32 : The Transpose
Determine .
is undefined.
is undefined.
is a two-by-three matrix. It follows that its transpose, , the result of switching rows with columns, is a three-by-two matrix. Since and have different dimensions, is an undefined expression.