MEDIUM
JEE Main/Advance
IMPORTANT
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If A is a diagonal matrix of order 3×3 is commutative with every square matrix of order 3×3 under multiplication and trA=12 then the value of dt.A is.

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Important Questions on Matrices

EASY
JEE Main/Advance
IMPORTANT
If A is a square matrix of order 3 such that A=2, then adjA-1-1 is
MEDIUM
JEE Main/Advance
IMPORTANT
If A and B are two matrices of order 3 such that AB=O and A2+B=I, then trA2+B2 is equal to.
HARD
JEE Main/Advance
IMPORTANT
If a,b and c are integers, then number of matrices A=abcbcacab which are possible such that AAT=I is.
HARD
JEE Main/Advance
IMPORTANT
Let A=aij be 3×3  matrix and B=bij be 3×3 matrix such that bij is the sum of the elements of ithrow of A except aij. If detA=19, then the value of detB is .
MEDIUM
JEE Main/Advance
IMPORTANT
A square matrix M of order 3 satisfies M2=I-M,  where I is an identity matrix of order 3. If Mn=5I-8M, then n is equal to.
HARD
JEE Main/Advance
IMPORTANT
Let A=aij3×3, B=bij3×3  and C=cij3×3 be any three matrices, where bij=3i-jaij and cij=4i-jbij. If det.A=2,  then detBC  is equal to .
MEDIUM
JEE Main/Advance
IMPORTANT
If A is a square matrix of order 2×2  such that A=27, then sum of the infinite series A+12A+12A+18A+...is equal to.
MEDIUM
JEE Main/Advance
IMPORTANT
If A is a square matrix of order 2 and detA=10, then trA2-trA2 is equal to.