15220723
| Question | Answer |
| Define a matrix | An array of numbers |
| Each entry (number) is called a what? | An element |
| Matrices can represent what? | Coordinates |
| What is the order of a matrix? | Number of rows and number of columns (R x C) |
| Rows are.... | Vertical down the side |
| Columns are.... | Horizontal along the top |
| We can only add or subtract matrices if they are.... | In the same order |
| To add or subtract matrices, we... | Add or subtract the corresponding elements |
| If we multiply a matrix by an integer, we... | Multiply all elements by that integer |
| We can only multiply matrices together if.... | The number of columns in A = number of rows in B (e.g. (2x2) and (2x3) is compatible as the inside numbers are both 2) |
| We can determine the order of the image (answer) by.... | Putting together the number of rows in A and the number of columns in B (e.g. (2x2) and (2x3) gives an order of (2x3) due to the outside numbers being put together) |
| What happens if both inside numbers are different? | We can't multiply the matrices |
| What method allows us to easily see what we are multiplying? | On matrix "A" circle the individual columns are on matrix "B" circle the individual rows. Now to work out the top left for example you multiply the top column numbers by the left row numbers (individually) |
| In general, matrices are not what? | Commutative (AB does not equal BA, however there are some exceptions),. |
| A square matrix has.... | The same number of rows as columns |
| A zero matrix is... | A matrix with all elements as 0 |
| An identity matrix is... | A square matrix with 1's going diagonally and 0's going everywhere else |
| Essentially, what integer does an identity matrix act as? | 1 |
| What is an inverse matrix? | A matrix which reverses the effect of the other (AA^-1=I , A^-1A=I , which are commutative) |
Want to create your own Flashcards for free with GoConqr? Learn more.