00:01
In this question we have to compute the inverse of matrix a.
00:05
A is having the entries 0, 2, 2, 1, 1, 1 and 0, 1, 2.
00:13
Okay.
00:14
So to find a inverse, let us see how we are going to do.
00:20
We need the determinant of a.
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So let us calculate.
00:23
So this will be 0 times 2 minus 1 minus 2 times.
00:32
This will be 2 minus 0 plus 2 times.
00:38
It will be 1 minus 0.
00:40
So this is equals to 0 minus 4 plus 2.
00:46
This is what i will get.
00:48
So this comes out to be equals to determinant of a equals to minus 4 plus 2.
00:54
It will be equals to minus 2.
00:56
Now we have to find out what is the adjoint of a.
01:01
Okay.
01:01
So for adjoint of a, i will write here for 0, adjoint will be given by minus 1 raised to the position is 1, 1.
01:13
So i will get here 1 plus 1.
01:15
Now you see, if you have first row and first column, we are going to get the determinant as 2 minus 1, which will be 2.
01:26
Then minus 1 raised to 1 plus 2.
01:30
And similarly, here it will be equals to 2 minus 0, then minus 1 raised to 1 plus 3.
01:39
And this will be equals to 1 minus 0, then minus 1 raised to 2 plus 1.
01:48
And this will be 4 minus 2, 4 minus 2.
01:54
Then i will get minus 1 raised to 2 plus 2.
01:57
And this will be 0.
02:01
Then minus 1 raised to 2 plus 3.
02:05
And here i will get 0 again.
02:10
Then minus 1 raised to 3 plus 1.
02:14
And it will be equals to 2 minus 2.
02:18
Then minus 1 raised to 3 plus 2...