Sep 8, 2015 · Matrix multiplication is defined so that it works right to left, just like function composition. This allows matrices to represent linear transformations more intuitively. It's also why we …

Dec 19, 2020 · Multiple sources tell me that I can't do multiplication or addition with matrix of different sizes. You can't add matrixes of different sizes as stated by @meshal.

Nov 6, 2015 · In my math lectures, we talked about the Gram-Determinant where a matrix times its transpose are multiplied together. Is $A A^\mathrm T$ something special for any matrix $A$?

Sep 28, 2019 · Yes, this is why it is called the identity matrix. Any matrix multiplied by the identity matrix is the original matrix, just as the multiplicative identity for $\mathbb {R}$ is $1$.

Jan 11, 2018 · Matrix multiplication is associative, so you can do it in whichever order you like. You can prove it by writing the matrix multiply in summation notation each way and seeing they match.

Dec 15, 2017 · Matrix multiplication is basically multiplying rows with columns, so the length of the rows of the first matrix need to be the same as the length of the columns of the second matrix. You can do …

Mar 4, 2015 · I have three 3D coordinate frames: O, A and B, as shown below. I want to know the rotation matrix RAB between A and B, that is the rotation that is required, with respect to the frame A, …

Jun 17, 2017 · This might be a very stupid question, but I do not seem to understand why I would multiple a matrix with its transpose. I am not a mathematician, but I am very interested in …

Asking why matrix multiplication isn't just componentwise multiplication is an excellent question: in fact, componentwise multiplication is in some sense the most "natural" generalization of real multiplication …

If you partition after x rows in first matrix , you've to partition after x columns (not rows ) in the second matrix. Otherwise while multiplying you'll have to multiply mn block with another mn block which is …