03 आव्यूह
अभ्यास 03
Question:
Find 1/2(A+) and 1/2(A−), when A=
Answer:
- Find AT:
AT =
- Find 1/2(A + AT):
1/2(A + AT) =
- Find 1/2(A - AT):
1/2(A - AT) =
Question:
If A= and B=, then verify that (i)=+ (ii)=−
Answer:
(i) A+B =
(A+B)T =
AT =
BT =
AT + BT =
Therefore, (A+B)T = AT + BT
(ii) A-B =
Question:
If (i) A=, then verify that A′A=I (ii) A=, then verify that A′A=I
Answer:
(i) A’A =
Since cos2α + sin2α = 1, A’A =
which is the identity matrix I.
(ii) A’A =
Since sin2α + cos2α = 1, A’A =
which is the identity matrix I.
Question:
Find the transpose of each of the following matrices: (i) (ii) (iii)
Answer:
(i)
(ii)
(iii)
Question:
If A=, then A+A′=I, if the value of α is A π/6 B π/3 C n D 3π/2
Answer:
A π/6
A=
A′=
A+A′=
A+A′=
Therefore, A+A′=I and the value of α is A π/6.
Question:
For the matrices A and B, verify that (AB)′=B′A′ where (i) A=,B= (ii) A=,B=
Answer:
(i) A=, B=
Step 1: Calculate AB
Step 2: Calculate (AB)′
Step 3: Calculate B′
Step 4: Calculate B′A′
Therefore, (AB)′=B′A′.
(ii) A=, B=
Step 1: Calculate AB
Step 2: Calculate (AB)′
Question:
For the matrix A=, verify that (i) (A+A′) is a symmetric matrix (ii) (A−A′) is a skew symmetric matrix.
Answer:
(i) To verify that (A+A′) is a symmetric matrix, we need to show that it is equal to its transpose.
A+A′ =
=
A′+A =
=
Since A+A′ = A′+A, it is a symmetric matrix.
(ii) To verify that (A−A′) is a skew symmetric matrix, we need to show that it is equal to its negative transpose.
A−A′ =
=
A′−A = <math xmlns = “http://www.w3.org/1998
Question:
If A,B are symmetric matrices of same order, then AB−BA is a , A Skew symmetric matrix B Symmetric matrix C Zero matrix D Identity matrix
Answer:
Answer: C Zero matrix
Question:
Express the following matrices as the sum of a symmetric and a skew symmetric matrix: (i) (ii) (iii) (iv)
Answer:
(i)
Symmetric Matrix:
Skew Symmetric Matrix:
(ii)
Symmetric Matrix:
Skew Symmetric Matrix:
(iii)
Question:
(i) Show that the matrix A= is a symmetric matrix (ii) Show that the matrix A= is a skew symmetric matrix.
Answer:
(i) A matrix A is symmetric if A = AT, where AT is the transpose of A.
Let A =
Then, AT =
Since A = AT, the matrix A is symmetric.
(ii) A matrix A is skew symmetric if A = -AT, where AT is the transpose of A.
Let A =
Then, AT =
Since A = -AT, the matrix A is skew symmetric.
Question:
If A′= and B=, then verify that: (i)(A+B)′=A′+B′ (ii)(A−B)′=A′−B′
Answer:
(i) To verify that (A+B)′=A′+B′, we need to calculate (A+B)′ and A′+B′ separately and then compare them.
(A+B)′ =
A′+B′ =
Since (A+B)′=A′+B′, we can conclude that (i) is true.
(ii) To verify that (A−B)′=A′−B′, we need to calculate (A−B)′ and A′−B′ separately and then compare them.
(A−B)′ =
A′−B′ =
Since (A−B)′=A′−B′, we can conclude that (ii) is true.
Question:
If A′= and B=, then find (A+2B)′.
Answer:
Step 1: Add A and 2B to get (A + 2B) A + 2B =
Step 2: Find the transpose of (A + 2B) (A + 2B)′ =
जेईई अध्ययन सामग्री (गणित)
01 संबंध एवं फलन
02 व्युत्क्रम त्रिकोणमितीय फलन
03 आव्यूह
04 सारणिक
05 सांत्यता और अवकलनीयता
06 अवकलज का अनुप्रयोग
07 समाकलन
08 समाकलन का अनुप्रयोग
09 वैक्टर
10 त्रिविमीय ज्यामिति का परिचय
11 रैखिक प्रोग्रामिंग
12 प्रायिकता