Given:
|4 -2| X = 2|-4 -4|
|-1 1| | 2 2|
What is X?
I solved this and couldn't get an answer - that is, the result was undefined/null, as it didn't like how the multiplication worked. I got this for every way I tried doing it, including by transposing the matrices and solving as per usual solve equation.
Is it actually just an equation with no answer, or am I missing something?
If you write this as
AX = B
then
X = A-1B
A-1 =
(1 1)
(1 2)
now just crank it out.
oops - misspoke:
A-1 =
1/2 (1 2)
(1 4)
So, X =
(0 0)
(4 4)
see
http://www.wolframalpha.com/input/?i=(inverse+%7B%7B4,-2%7D,%7B-1,1%7D%7D)*(2%7B%7B-4,-4%7D,%7B2,2%7D%7D)
Oooh, I forgot about inverse matrices. Thank you!
It seems like there might be an error in the problem you provided. When multiplying matrices, the number of columns in the first matrix must equal the number of rows in the second matrix in order for the multiplication to be defined.
In this case, the first matrix is a 2x2 matrix and the second matrix is also a 2x2 matrix. Therefore, the number of columns in the first matrix does not equal the number of rows in the second matrix, which means that matrix multiplication is not defined for these matrices.
Hence, there is no solution to the equation you provided.