Q. 30
If A=
then A-1=?
A. A
B. –A
C. Adj A
D. –adj A
Answer :
A=
│A│= cos2
- (-sin2
)
= cos2
+ (sin2
)
= 1 ---------- (I)
We know that A-1= 
adj A
= adj A [From I]
Rate this question :
Range of Quadratic/quadratic & linear/Linear functions45 mins
Functional Equations - JEE with ease48 mins
Immune System Disorders60 mins
Female reproductive system58 mins
Female reproductive system46 mins
Rotational Kinetic Energy43 mins
Interactive Quiz | Questions based on torque & angular momentum44 mins
Interactive Quiz: Important Questions Based on Moment of Inertia35 mins
Female Reproductive System | Interactive Quiz39 mins
Pure Rolling49 mins
Find the adjoint of each of the following Matrices and Verify that (adj A) A = |A| I = A (adj A)
Verify that (adj A) A=|A| I=A (adj A) for the above matrices.
RD Sharma - Volume 1Solve the following system of equations by matrix method:
2y – z = 1
x – y + z = 2
2x – y = 0
RD Sharma - Volume 1Find the adjoint of each of the following Matrices.
Verify that (adj A) A=|A| I=A (adj A) for the above matrices.
RD Sharma - Volume 1Solve the following system of equations by matrix method:
3x + 7y = 4
x + 2y = – 1
RD Sharma - Volume 1Solve the following system of equations by matrix method:
x + y –z = 3
2x + 3y + z = 10
3x – y – 7z = 1
RD Sharma - Volume 1For the matrix A= 
, show that A(adj A)=O.
Find the adjoint of each of the following Matrices and Verify that (adj A) A = |A| I = A (adj A)
Verify that (adj A) A=|A| I=A (adj A) for the above matrices.
RD Sharma - Volume 1If 
find 
and hence solve the system of equation 
If 
, show that adj A=3AT.
