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

Related Further Mathematics A Level answers

All answers ▸

The curve C has parametric equations x=cos(t)+1/2*sin(2t) and y =-(1+sin(t)) for 0<=t<=2π. Find a Cartesian equation for C. Find the volume of the solid of revolution of C about the y-axis.


What is the root of i? give all solutions


Show, using the focus-directrix property for an ellipse, that PS +PS'=2a where P is a point on the ellipse and S and S' are the two foci.


You have three keys in your pocket which you extract in a random way to unlock a lock. Assume that exactly one key opens the door when you pick it out of your pocket. Find the expectation value of the number of times you need to pick out a key to unlock.