SME
Grade 12 Math
Systems in three variables, matrices and determinants
The main lesson, then each kind of problem it solves.
Systems in three variables, matrices and determinants
Main lesson
A matrix times a vector
Use this for “Multiply [[2, 1], [3, 4]] by the column (5, −1).”
Determinant of a 3 × 3 matrix
Use this for “Find the determinant of [[2, 0, 1], [1, 3, 2], [1, 1, 4]].”
Inverse of a 2 × 2 matrix
Use this for “Find the inverse of [[4, 7], [2, 6]].”
Solving a system with A⁻¹
Use this for “Solve 3x + 2y = 7 and 5x + 4y = 13 with the inverse matrix.”
Cramer’s rule for two equations
Use this for “Solve 2x + 3y = 13 and x − y = −1 by Cramer’s rule.”