00:01
So here the system of equations in matrix form is 1 2 minus 1 minus 7 5 1 1 8 minus 1 2 multiplied by x 1 x2 x2 equals to solution matrix which is 1 minus 1 0.
00:30
Here it is of the form a x is equal to b right so determinant of a becomes 1 multiplied by 5 1 minus 1 2 minus 2 multiplied by determinant minus 7 1 8 2 plus minus 1 multiplied by determinant minus 7, 5, 8, minus 1.
01:09
What are the solving? we get, this is equal to 1 multiplied by 5 multiplied by 2, that is 10 minus 1 minus 1, that is minus 1.
01:23
Similarly, minus 2, minus 14 minus 8, minus 1, 7 minus 40.
01:31
On simplifying this, we get this is equal to 88.
01:40
Now we'll find a1.
01:44
A1 is the matrix which we form by replacing first column of a with solution vector b.
01:52
That is, a1 becomes solution vector 1 minus 1, 0.
01:58
Remaining all remains same, that is 2, 5 minus 1, minus 1, 2.
02:04
As ever, we'll find the value of determinant a1...