This self-directed task uses the CAS functionality of TI-nspire to determine rules for adding and subtracting matrices with the same dimensions, including confirmation of the associative and commutative law for addition. Students are then guided to investigate adding and subtracting matrices with different dimensions.
Add and subtract matrices with the same dimensions
Verify the commutative and associated laws for the addition of matrices.
Determine that matrices must share the same dimensions if they are to be added / subtracted.
Associative law, Commutative law, dimensions, matrix
About the Lesson
In this activity students define a number of matrices consisting of variables so that when the matrices are added or subtracted the algebraic result in each element of the matrix provides the general rule. The task contains the appropriate calculator instructions followed by a series of scaffolded questions to guide students through the investigation.