1 votes 1 votes A $n\times n$ matrix $A$ is said to be $symmetric$ if $A^T=A$. Suppose $A$ is an arbitrary $2\times 2$ matrix. Then which of the following matrices are symmetric (here $0$ denotes the $2\times 2$ matrix consisting of zeros): $A^TA$ $\begin{bmatrix} 0&A^T \\ A & 0 \end{bmatrix}$ $AA^T$ $\begin{bmatrix} A & 0 \\ 0 & A^T \end{bmatrix}$ Others cmi2018-datascience matrix linear-algebra discrete-mathematics + – soujanyareddy13 asked Jan 29, 2021 edited Feb 4, 2021 by soujanyareddy13 soujanyareddy13 545 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes Well, the best way to go is to have a quick look at the options. The first one says $A^TA$. Let us transpose it. So, $(A^TA)^T = (A)^T *(A^T)^T = A^TA$ So, option s stands true for the symmetricity principle. i_am_tatha answered Mar 7, 2021 i_am_tatha comment Share Follow See all 2 Comments See all 2 2 Comments reply Rishabhsharma98 commented Jul 6, 2021 reply Follow Share In the answer key they have mentioend that (a), (b) and © are correct, can you please explain how (b) is correct and (d) is not? 1 votes 1 votes anniechakraborty commented Nov 23, 2021 reply Follow Share Yes I have the same issue. I think the answer might be wrong. It should be a, c and d. 0 votes 0 votes Please log in or register to add a comment.