03 ମ୍ୟାଟ୍ରିକ୍ସ

ବ୍ୟାୟାମ 03

Question:

Find 1​/2(A+ A T ) and 1​/2(A− A T ), when A=[0ab-a0c-b-c0]

Answer:

  1. Find AT:

AT = [0-a-ba0cb-c0]

  1. Find 1/2(A + AT):

1/2(A + AT) = [0000ac0c0]

  1. Find 1/2(A - AT):

1/2(A - AT) = [0ab-a0-c-bc0]

Question:

If A=[-123579-211] and B=[-41-5120131], then verify that (i) (A+B) T = A T + B T (ii) (A-B) T = A T B T

Answer:

(i) A+B = [-53-2699-142]

(A+B)T = [-56-1394-292]

AT = [-15-2271391]

BT = [-411123-501]

AT + BT = [-56-1394-292]

Therefore, (A+B)T = AT + BT

(ii) A-B = [</

Question:

If (i) A=[cosαsinα-sinαcosα], then verify that A′A=I (ii) A=[sinαcosα-cosαsinα], then verify that A′A=I

Answer:

(i) A’A = [cos2αsinαcosαsinαcosαsin2α]

Since cos2α + sin2α = 1, A’A = [1001]

which is the identity matrix I.

(ii) A’A = [sin2αsinαcosαsinαcosαcos2α]

Since sin2α + cos2α = 1, A’A = [1001]

which is the identity matrix I.

Question:

Find the transpose of each of the following matrices: (i) [51/2-1] (ii) [1-123] (iii) [-156√35623-1]

Answer:

(i) [51/2-1]

(ii) [12-13]

(iii) [-1√3255366-1]

Question:

If A=[cosα−sinαsinαcosα], 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=[cosπ/6−sinπ/6sinπ/6cosπ/6]

A′=[cosπ/6sinπ/6−sinπ/6cosπ/6]

A+A′=[2cosπ/6002cosπ/6]

A+A′=[1001]

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=[1-43],B=[-121] (ii) A=[012],B=[157]

Answer:

(i) A=[1-43], B=[-121]

Step 1: Calculate AB

[-1-85]

Step 2: Calculate (AB)′

[-1-85]

Step 3: Calculate B′

[-121]

Step 4: Calculate B′A′

[1-43]

Therefore, (AB)′=B′A′.

(ii) A=[012], B=[157]

Step 1: Calculate AB

[5717]

Step 2: Calculate (AB)′

[5717</m

Question:

For the matrix A=[1567], 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′ = [1567]+[1657]

= [2111114]

A′+A = [1657]+[1567]

= [2111114]

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′ = [1567]-[1657]

= [0-110]

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) [351-1] (ii) [6-22-23-12-13] (iii) [33-1-2-21-4-52] (iv) [15-12]

Answer:

(i) [351-1]

Symmetric Matrix: [244-2]

Skew Symmetric Matrix: [11-11]

(ii) [6-22-23-12-13]

Symmetric Matrix: [402020204]

Skew Symmetric Matrix: [220-21-101-2]

(iii) [33-1-2-21-4<mtd

Question:

(i) Show that the matrix A=[1-15-121513] is a symmetric matrix (ii) Show that the matrix A=[01-1-1011-10] is a skew symmetric matrix.

Answer:

(i) A matrix A is symmetric if A = AT, where AT is the transpose of A.

Let A = [1-15-121513]

Then, AT = [1-15-121513]

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 = [01-1-1011-10]

Then, AT = [0-1110-1-110]

Since A = -AT, the matrix A is skew symmetric.

Question:

If A′=[34-1201] and B=[-121123], 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)′ = [261044134]

A′+B′ = [261044134]

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)′ = [42-1-10-21-12]

A′−B′ = [42-1-10-21-12]

Since (A−B)′=A′−B′, we can conclude that (ii) is true.

Question:

If A′=[-2312] and B=[-1012], then find (A+2B)′.

Answer:

Step 1: Add A and 2B to get (A + 2B) A + 2B = [-3636]

Step 2: Find the transpose of (A + 2B) (A + 2B)′ = [-3366]

JEE ଅଧ୍ୟୟନ ସାମଗ୍ରୀ (ଗଣିତ)

01 ସମ୍ପର୍କ ଏବଂ କାର୍ଯ୍ୟ

02 ଓଲଟା ଟ୍ରାଇଗୋନେଟ୍ରିକ୍ କାର୍ଯ୍ୟଗୁଡ଼ିକ

03 ମ୍ୟାଟ୍ରିକ୍ସ

04 ନିର୍ଣ୍ଣୟକାରୀ

05 ନିରନ୍ତରତା ଏବଂ ଭିନ୍ନତା

06 ଡେରିଭେଟିକ୍ସର ପ୍ରୟୋଗ

07 ଇଣ୍ଟିଗ୍ରାଲ୍

08 ଇଣ୍ଟିଗ୍ରାଲ୍ସର ପ୍ରୟୋଗ

09 ଭେକ୍ଟର୍

10 ତିନୋଟି ଡାଇମେନ୍ସନାଲ୍ ଜ୍ୟାମିତି

11 ରେଖା ପ୍ରୋଗ୍ରାମିଂ

12 ସମ୍ଭାବନା