00:02
So here, a, b is invertible.
00:05
A and b are invertible.
00:07
Therefore, which implies modulus of ab is not equal to 0.
00:13
Mod ab is not equal to 0, which implies mod a multiplied by mod b is not equal to 0.
00:23
Since determinant of we know that determinant of ab is equal to, determinant of ab equal to determinant of a multiplied by determinant of b.
00:38
Determinant of a multiplied by determinant of b, which implies determinant of a is not equal to zero.
00:47
Determinant of a not equal to zero and determinant of b not equal to zero.
00:53
To 0 is not equal to 0 which implies that b is a invertible matrix invertible matrix so option one will be the true answer option one is the correct answer so for a square matrix a and b if a b is invertible then b will also be invertible that condition can also be applied the next one, let a is a square matrix.
01:27
So, a is a square matrix implies a square matrix implies a cube is equal to 1, i, that is identity matrix.
01:41
So, determinant of i is equal to 1.
01:44
As we know, determinant of i is equal to 1.
01:48
Hence, determinant of a cube is equal to, determinant of a cube is equal to, 1...