Consider the following statements in respect of two non-singular matrices $A$ and $B$ of the same order $n$:
- 1.$adj(AB) = (adjA)(adjB)$
- 2. $adj(AB) = adj(BA)$
- 3. $(AB) adj(AB) - |AB| I_n$ is a null matrix of order $n$
How many of the above statements are correct?
None
Only one statement
Only two statements
All three statements
Consider the following statements in respect of a non-singular matrix $A$ of order $n$:
1. $A(\text{adj}A^T) = A(\text{adj}A)^T$
2. If $A^2 = A$, then $A$ is identity matrix of order $n$
3. If $A^3 = A$, then $A$ is identity matrix of order $n$
Which of the statements given above are correct?
1 and 2 only
2 and 3 only
1 and 3 only
1, 2 and 3
How many four-digit natural numbers are there such that all of the digits are even?
625
500
400
256
If $\omega \neq 1$ is a cube root of unity, then what are the solutions of $(z-100)^3 + 1000 = 0$?
$10(1-\omega)$, $10(10-\omega^2)$, $100$
$10(10-\omega)$, $10(10-\omega^2)$, $90$
$10(1-\omega)$, $10(10-\omega^2)$, $1000$
$(1 + \omega)$, $(10 + \omega^2)$, $-1$