How do you find the determinant of a matrix?

Finding the matrix of a matrix can be done in 5 steps. Step 1 involves finding the determinant of the matrix, and putting this value aside for later. Step 2 finds the cofactors of each element. The cofactor of an element 'a' is the determinant of the matrix created by removing the row and column that contain the element 'a' from the original matrix. For step 3 we need to replace each element with its cofactor. For a 2 by 2 matrix, step 2 and 3 essentially swaps each element with its diagonal. Now, for the 4th step we transpose the matrix, which is basically making the rows into columns. This is like reflecting the matrix along its leading diagonal. For the last step, we multiply this result by 1 over the determinant that we calculated in step 1, and we have our matrix inverse!

LC
Answered by Lizzie C. Further Mathematics tutor

3925 Views

See similar Further Mathematics A Level tutors

Related Further Mathematics A Level answers

All answers ▸

Two planes have eqns r.(3i – 4j + 2k) = 5 and r = λ (2i + j + 5k) + μ(i – j – 2k), where λ and μ are scalar parameters. Find the acute angle between the planes, giving your answer to the nearest degree.


How do I sketch accurate graphs for rational functions in a short amount of time? (I.e. A step by step guide of sketching graphs)


Can you show me how to solve first order differential equations using the integrating factor method?


Find the complex number z such that 5iz+3z* +16 = 8i. Give your answer in the form a + bi, where a and b are real numbers.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning