Matrices: watch it solved step by step
Determinant, inverse, transpose, products and eigenvalues of 2×2 and 3×3 matrices, with a check. Level: A-level / University. Type any problem of this kind and the Lab works it out and animates every move, with a plain-words explanation of why.
Worked example: [[1, 2], [3, 4]] * [[0, 1], [1, 0]]
- The matrices. To multiply matrices, each entry of the answer is a row of A times a column of B: multiply along, add up.
- Row 1 times each column. Take the first row of A and pair it with each column of B.
- The other rows. Repeat for every row of A.
- The product. Put the entries together.
- Is it the same the other way round?. Matrix multiplication is not commutative: AB and BA are usually different.
Answer: AB = [2, 1], [4, 3]
Practise matrices with problems the Lab marks for you.