MATH- TEST PAPERS
Tuesday, 20 January 2026
Mixed b/c/p/m
Friday, 16 January 2026
b. aom
Type-1)
1) lim ₓ→₀ (7x²-5x+1). 1
2) limₓ→₀ (2x³+3x+4)/(x²+3x+2). 2
3) limₓ→₃√(2x+3)/(x+3). 1/2
4) limₓ→₁ √(x+8)/√x. 3
5) lim ₓ→₁(x²+1)/(x+1). 1
6) lim ₓ→ₐ (√a+√x)/(a+x). 1/√a
7) limₓ→₁{1+(x-1)²}/(1+x²). 1/2
8) lim ₓ→₂ (3x²-x+1)/(x-1). 11
9) limₓ→₁ (4-x). 3
10) lim ₓ→₀(ax²+b)/(cx+d). b/d
11) limₓ→_₁(x³ - 3x +1)/(x-1) -3/2
12) limₓ→₀ (3x+1)/(x+3). 1/3
Type: 2. *******
1) lim ₓ→₁ (x²-1)/(x-1). 2
2) limₓ→₋₅ (2x²+9x-5)/(x+5). -11
3) limₓ→₃(x²-4x+3)/(x²-2x-3). 1/2
4) limₓ→₄ (x²-16)/(√x -2). 32
5) limₓ→₀ {(a+x)³-a³}/x. 3a²
6) lim ₓ→₁(x-1)/(2x²-7x+5). -1/3
7) lim ₓ→₁ (x²-√x)/(√x-1). 3
8) limₓ→₃(x²-9)/{1/(x-3)+1/(x+3)}. 6
9) limₓ→₁ (x-1)/(2x²-7x+5). -1/3
10) limₓ→₃ (x²-7x+12)/(x²-9). -1/6
11) limₓ→₂ (7x²-11x-6)/(3x²-x-10). 17/11
12) limₓ→₂ (x³-8)/(x-2). 12
13) limₓ→_₁(2x²+5x+3)/(x³+1). 1/3
14) limₓ→₂ x²(x²-4)/(x-2). 16
15) limₓ→₂{(x⁸-16)/(x⁴-4)+(x²-9)/(x-3)}. 25
16) limₓ→₂ (x-2)/(√x -√2). 2√2
17) limₓ→₀ {(1+x)²-(1-x)²}/2x. 2
18) limₓ→₁ (x²+5x-6)/(x²-3x+2). -7
19) lim ₓ→₁/₂{(8x-3)/(2x-1) - (4x²+1)/(4x²-1)}. 7/2
20) limₓ→₃(x²+x-12)/(x-3). 7
21) limₓ→₁(x²+4x-5)/(x-1). 6
22) limₓ→₀ {(1+x)²-1}/x. 2
23) limₓ→₂(x²-5x+6)/(x²-3x+2). -1
24) limₓ→₂(x²+x-6)/(x²-x-2). 5/3
25) limₓ→₂(x²-5x+6)/(x²-7x+10) 1/3
26) limₓ→₃(x²+2x-15)/(x²-2x-3). 2
27) limₓ→₁(x³-1)/(x²-1). 3/2
28) limₓ→₂{1/(x-2) - 1/(x²-3x+2)}. 1
29) limₓ→₁(x²-3x+2)/(x³-4x+3). 1
30) limₓ→₀{(4+3x)³-8x²}/{4(4-x)²}.1
31) limₓ→₂(2x²-3x+7)/(x³+5x+1) 9/19
32) limₓ→_₁(2x²+5x+3)/(x³+1). 1/3
33) limₓ→₁(2x⁴-3x+1)/(x³-5x²+4x). -5/3
34) limₓ→₃(x³-8x²+45))(2x²-3x-9). -7/3
35) limₓ→₃(x³-6x-9)/(x⁴-81). 7/36
36) limₓ→√₂ (x⁴-4)/(x²+3x√2-8). 8/5
37) limₓ→₁(x⁴-3x³+2)/(x³-5x²+3x+1) 5/4
38) limₓ→₁{(2x-3)(√x -1)}/(2x²+x-3) -1/10
39) limₓ→₃(x²-9){1/(x+3) + 1/(x-3)} 6
40) limₓ→₂(x³-6x²+11x-6)/(x²-6x+8) 1/2
41) limₓ→₁/₂ (8x³-1)/(16x⁴-1) 3/4
42)limₓ→₄(x²-x-12)¹⁸/(x³-8x²+16x)⁹ 7¹⁸/4⁹
43) limₓ→₁{1/(x²+x-2) - x/(x³-1)}. -1/9
44) limₓ_₃(x³-7x²+15x-9)/ (x⁴-5x³+27x-27) 2/9
45) limₓ→√₂. (x⁹- 3x⁸+ x⁶- 9x⁴- 4x²- 16x+84)/(x⁵-3x⁴-4x+12). (8√2-31)/(√2-3)
46) limₓ→₃ (x⁴- 81)/(x²-9). 18
47) limₓ→₃(x²-x-6)/(x³-3x²+x-3). 1/2
48) limₓ→₋₂ (x³+x²+4x+12)/ (x³-3x+2). 4/3
49) limₓ→₁(x³+3x²-6x+2)/ (x³+3x³-3x-1). 1/2
50) limₓ→₁(x⁴-3x³+2)/(x³-5x²+3x+1) 5/4
51) limₓ→₂ (x³+3x²-8x-2)/(x³-x-6). 15/11
52) limₓ→₂ (x⁴ -16)/(x-2). 32
53) limₓ→₁{(x-2)/(x²-x) - 1/(x³ -3x²+2x)}. 2
54) limₓ→₂ {1/(x-2) - 2(2x-3)/(x³- 3x² +2x)}. -1/2
55) lim ₕ→₀ {f(1+h)-f(1)}/h, when f(x)= 1/x. -1
Continue.........
Type: 3. ------------
1) limₙ→₀{√(x+n) -√(x)}/n. 1/2√x
2)limₓ→₀ {√(1+x) - √(1+x²)}/x. 1/2
3) ltₓ→₀{√(1+x) -√(1+x²}/{√(1-x²)-√(1-x)}. 1
4) limₓ→ₐ{√(a+2x)-√(3x)}/ {√(3a+x) -2√(x)}, a≠ 0. 2/3√3
5) limₙ→₀ 1/n{1/√(x+n) - 1/√(x)}. -1/(2x√x)
6) limₓ→₀ {√(1+x) - 1}/x. 1/2
7) limₓ→ₐ{√(x) - √(a)}/(x-a). 1/2√a
8) limₓ→₄ {3 -√(5+x)}/(x-4). -1/6
9) limₓ→₀{√(x+2) - √(2)}/x. 1/2√2
10) limₓ→₀ x/{√(1-x)- 1}. 2
11) limₓ→₀ {√(1+x) -√(1-x)}/2x. 1/2
12)
13) limₓ→₀ {√(1+x+x²) -1 }/x. 1/2
14) limₓ→₀{√(1-x³) -√(1+x³)}/x². 0
15) limₓ→₄ {3-√(5+x)}/{3-√(5-x). 1/3
16) limₓ→₃{3-√(6+x)}/{√3 -√(6-x). -1/√3
17) limₓ→₀{√(1+x) -√(1+x²)}/{√(1-x²) - √(1-x)}. 1
18) limₓ→₂(x²-4)/{√(3x-2)-√(x+2)}. 8
19) limₓ→₃{√(3x+7)-√(7x-5)}/{√(5x-6) - √(2x+3)}. - 1
20) limₓ→₁{√(x+8)-√(8x+1)}/{√(5-x)- √(7x-3)}. 7/12
21) limₓ→₁ {³√(x+7)- ³√(7x+1)}/(x-1) 1 - ³√7
22) limₓ→₂{2-√(2+x)}/{³√2- ³√(4-x)} - 3/³√16
23) limₓ→₀ x/{√(a+x)-√(a-x)}. √a
24) limₓ→₄ (x²-16)/{√(x²+9) -5} 10
25) limₓ→ₐ{√(a+2x)-√(3x)}/{√(3a+x)- 2√x} 2/3√3
26) limₓ→₁{(2x-3)(√x -1)}/(2x²+x-3) -1/10
27) limₓ→√₁₀ {√(7-2x)-(√5-√2)}/(x²-10). (√5+√2)/6√10
28) limₓ→₂ {√(x²+1)-√5}/(x-2) 2/√5
29) limₓ→₂ (2-√x)/(4-x). 1/4
30) limₓ→ₐ (x-a)/(√x - √a). 2√a
31) limₓ→₂ (x-2)/(√x-√2). 2√2
32) limₓ→₃ {√(x-3)+√x -√3}/√(x² -9) -1
Continue.......
Type : 4
1) limₓ→₂(x¹⁰ - 1024)/(x-2). 5120
2) limₓ→₁ (xᵐ -1)/(x-1) m
3) limₓ→₃ (x⁵-243)/(x²-9). 135/2
4)limₓ→ₐ(x⁵-a⁵)/(x³-a³). 5a²/3
5) limₓ→₅ (x⁴-625)/(x³-125). 20/3
6) limₓ→₂ (x¹⁰ -1024)/(x⁵ -32). 64
7) limₓ→₉ (x³/² -27)/(x-9). 9/2
8) limₓ→ₐ(x³/⁵-a³/⁵)/(x¹/³-a¹/³). 9/
a⁴/¹⁵/5
10) limₓ→₁(xᵐ -1)/(xⁿ -1) m/n
11) limₓ→ₐ (x√x- a√a)/(x-a) 3√a/2
12) limₓ→₂ (x⁷-2⁷)/(x³-2³). 112/3
13) limₓ→₀ {(1+x)ⁿ -1}/x. - n
14)limₓ→¹ {(1+x)⁶ -1}/{(1+x)² -1}. 3
15) lim ₓ→ₐ(x²⁾⁷- a²⁾⁷)/(x-a) 2/7a⁵⁾⁷
16) lim ₓ→₋₁/₂ (8x³+1)/(2x+1). 3
17) limₓ→ₐ{(x+2)⁵/² -(a+2)⁵/²}/(x-a) 5/2 √(a+2)³
18) lim ₓ→₂ (x-2)/(³√x - ³√2). 3(2²⁾³)
19) If lim ₓ→₂ (xⁿ - 2ⁿ)/(x-2)= 80 and n∈ ℕ find n 5
20) If lim ₓ→₁(x⁴-1)/((x-1)= lim ₓ→k (x³ - k³)/(x² - k²). Find k 8/3
21) If limₓ→_ₐ (x⁹+a⁹)/(x+a) = 9, then find the value of a. ±1
22) limₓ→³ (xⁿ-3ⁿ)/(x-3) =108 and if n is positive integer find n. 4
Continue........
Type : 5
1)lim→₀ (e⁻ˣ -1)/x. -1
2) limₓ→₀ (eᵃˣ-1)/ax. 1
3) limₓ→₀ (eᵃˣ-1)/mx. a/m
4) limₓ→₀ (e⁵ˣ -1)/3x. 5/3
5) limₓ→₀ (eᵃˣ - eᵇˣ)/x. a-b
6) limₓ→₀ (e⁷ˣ - e³ˣ -e⁴ˣ +1)/x². 12
7) limₙ→₀{ ₑ(x+n)² - ₑx²)}/n. 2x
8) lim ₓ→⁰ (eˣ- e)/(x-1). e
9) limₓ→₀ (ₑlog x ₋ ₁)/ₑˣ⁻¹ ₋ ₁) 1
10) lim ₓ→₀ (eˣ - e²)/(x-2). e²
11) limₓ→₀ (e⁷ˣ - 1)/9x 7/9
12) lim ₓ→₀ (eˣ - e⁻ˣ)/x. 2
13) limₓ→₀ (e¹⁵ˣ - e⁷ˣ)/x. 8
14) limₓ→₀ (e⁷ˣ + e⁵ˣ -2)/x. 12
Type : 6
1) limₓ→₀ (3⁵ˣ - 1)/x. 5 log 3
2) limₓ→₀ (2³ˣ -1)/x. 3 log 2
3) limₓ→₀ (2ᵃˣ - 3 ᵇˣ)/x. alog 2-b log 3
4) limₓ→₀ (12ˣ -3ˣ- 4ˣ +1)/x² log 3. Log 4
5) limₓ→₀(aˣ - bˣ)/x. log(a/b)
6) limₓ→₀ (10ˣ -2ˣ- 5ˣ +1)/x². log 5. log 2
Continue......
Type : 7
1) lim ₓ→₀ {log(1+7x)}/x. 7
2) limₓ→₁ (log x)/(x-1). 1
3) limₓ→₀ {log(6+x)- log(6)}/x. 1/6
4) limₓ→₂ {log(x) - log(2)}/(x-2). 1/2
5) limₓ→ₑ (logx -1)/(x-e). 1/e
6) limₓ→₁(x²- x log x+ log x -1)/(x-1) 6
7) limₓ→₀ x{log(x+a) - log x}. a
8) limₓ→⁰ x{log(x+5) - log x}. 5
9) limₓ→₄ (x⁷/²- 4⁷/²)/{ log(x-3)} 112
Continue.......
Type: 8
1) limₓ→∞ (4x-3)/(2x+7). 2
2) limₓ→∞(3x²+2x-5)/(x²+5x+1). 3
3) limₓ→∞ (x³+6x²+1)/(x⁴+3). 0
4) limₓ→∞(3x³+x²-1)/(x²-x+7). ∞
5) limₓ→∞ (5x-6)/√(4x²+9). 5/2
6) limₓ→∞{√(3x²-1)-√(2x²-1)}/ (4x+3). (√3-√2)/4
7) limₓ→∞{√x √(x+c) -√x). c/2
8) limₓ→∞{√(x²+x+1) - √(x²+1)}. 1/2
9) limₓ→∞{(x+1)(2x+3)}/{(x+2)(3x+4)}. 2/3
10) limₓ→∞ {x - √(x² - x)}. 1/2
11) limₓ→∞{√(x²+5x+4)- √(x²-3x+4)}. 4
12) limₓ→∞ 2x{√(x²+1)-x}. 1
13) limₓ→∞{√(x²+1)-³√(x²-1)}/{ ⁴√(x⁴+1)- ⁵√(x⁴+1)}. 1
14) limₓ→∞(5x³-3x+1)/(7x³+2x²-2). 5/7
15) limₓ→_∞(5-6x²)/(1++2x-3x²) 2
16) limₓ→∞(x√x+√x -1)/(5√x+1) ∞
17) limₓ→∞ {(x+1)(2x+1)(3x+1)}/ {(x²+1)(5x-3)}. 6/5
18) limₓ→∞{1²+2²+...+x²}/{(x-2)(x+3)(x-4)}. 1/3
19) limₓ→∞{1+ 1/2 + 1/2²+.... to n terms}. 2
20) limₓ→∞{1+3+5+... to n terms}/(n² -1). 1
21) limₓ→∞{2+5+8... to(2n+1)}/{1+2+3+.... to n terms} 12
22) limₓ→∞(1.2+2.3+3.4+...to n terms)/{(3-n)(n+1)(n+2). -1/3
23) limₓ→∞{√(x²-2x+1) - √(x²-5x-3)}. 3/2
24) limₓ→∞ [³√x²{³√(x+1)- ³√x}] 1/3
25) limₓ→∞{(2x-1)³(x²+1)}²/{(x³-2x+1)(3x+1)}. 8/3
26) limₓ→∞{(2x³-x+1)²(x²-1)³}/ {(3x+1)⁴(2x⁴-3x+1)²}. 1/81
27) limₙ→∞ (1+3+....+n)/n². Or limₙ→∞ ∑n/n² 1/2
28) limₙ→∞ ∑n³/n⁴ 1/4
Monday, 29 December 2025
3rd sem
A) DEFINITION
A matrix is defined as a rectangular arrangement of numbers in rows and columns. e.g.,
A = 2 √3 4
1 √2 0
B = 2 3 1 ≺ row 1
5 6 0 ≺ row 2
0 9 4 ≺ row 3
| | |
col. 1 col.2 col.3
NOTE:
1) A matrix is always denoted by a capital letters, like A, B, C, ...etc.
2) The number which are listed within brackets are known as
" Elements or Entries or Members" of the matrix.
3) Generally [ ] or ( ) brackets are used to donate a matrix.
4) The horizontal lines are known as " ROWS " and vertical lines are known as " COLUMNS ". Thus the matrix A has two rows and three columns. We say to be a rectangular (since, the number of rows is different from number of columns) matrix of order 2x3 and B to be a square matrix or order 3x3 (since, the number of rows is same as the number of columns).
• In other words we can say A matrix having m rows and n columns is called a matrix of order m x n (read as m by n).
a₁₁ a₁₂ ........ a₁ⱼ ....... a₁ₙ
a₂₁ a₂₂ ....... a₂ⱼ ....... a₂ₙ
.... .... ....... .... ....... ....
aᵢ₁ aᵢ₂ ....... aᵢⱼ ...... aᵢₙ
... ... ...... ... ...... ...
aᵤ₁ aᵤ₂ ...... aᵤⱼ ...... aᵤₙ
OR
a₁₁ a₁₂ ........ a₁ⱼ ....... a₁ₙ
a₂₁ a₂₂ ....... a₂ⱼ ....... a₂ₙ
.... .... ....... .... ....... ....
aᵢ₁ aᵢ₂ ....... aᵢⱼ ...... aᵢₙ
... ... ...... ... ...... ...
aᵤ₁ aᵤ₂ ...... aᵤⱼ ...... aᵤₙ
The elements aᵢⱼ occurs in the ith row and jth column is called
(i j)-th element. For example, a₃₂ is the element of 3rd row and 2nd column.
The matrix written above is also denoted by the symbol (aᵢⱼ)ᵤₓₙ or [aᵢⱼ]ᵤₓₙ where i= 1, 2, 3, ....., m and j= 1, 2, 3, ....,n.
Different matrices are symbolised different capital letters as A, B, C etc.
REAL METRIX : if the elements of a matrix be all real then the matrix is called a real matrix.
B) SOME DEFINITION OF METRIX:
a) ROW MATRIX: A matrix whose elements are arranged in one row only is called a row matrix.
For examples, [a₁ a₂ a₃ ........aₙ] is a row matrix. Clearly, the order of the matrix is 1 x n.
b) COLUMN MATRIX: A matrix whose elements are arranged in one Column only is called a Column matrix. For example,
b₁
b₂
b₃
.
.
.
bᵤ is a column matrix. Clearly, the order of the matrix is m x 1.
c) NULL or ZERO MATRIX : A matrix whose every element is zero is called a null matrix or zero matrix. A null matrix is generally denoted by O. A null matrix of order u x n is denoted by Oᵤ ₓₙ
Example ) ( 0 0 0)
or 0 0 0 0 0
0 0 or 0 0 0
0 0 0
are all null matrix
d) SQUARE MATRIX: A matrix whose number of rows and columns are equal is called a square matrix. If number of rows = number of columns= n, then the matrix is called a square matrix of order n (or n x n square matrix). For example, a₁ b₁ c₁
a₂ b₂ c₂
a₃ b₃ c₃
is a square matrix of order 3 (or third order matrix).
DIAGONAL ELEMENTS: If A =[aᵢⱼ] be a square matrix, then elements where I = j are called diagonal elements and the straight line on which they lie is called the Principal diagonal or simply diagonal of the square matrix. For example, for the square matrix
1 3 5
4 6 8
2 7 4
is the diagonal elements are 1, 6, 4.
d) DIAGONAL MATRIX: A square matrix whose all the elements Except the elements in principal diagonal are zero is called a diagonal matrix. For example
a₁ 0 0
0 b₂ 0
0 0 c₃
is a diagonal matrix of order 3. And principal diagonal is a₁ b₂ c₃
2 0
0 3
is a diagonal matrix of order 2. And principal diagonal is 2 3.
NOTE:
1) A square matrix has two diagonals. The diagonal extending from left-hand top corner to right hand bottom corner is known as PRINCIPAL or MAIN or LEADING diagonal.
2) Atleast one element of the principal diagonal must be non-zero.
e) SCALAR MATRIX: A diagonal matrix whose elements on the principal diagonal are non-zero and all equal to each others is called scalar matrix for example
1) -2 0 2) 7 0 0
0 -2 0 7 0
0 0 7
f) UNIT or IDENTITY MATRIX: A scalar matrix whose elements on the principal diagonal are all 1 is called a unit or identify matrix. An unit matrix is generally denoted by I. Sometimes the order of the unit matrix is also written as suffix of I. For example. I₂ and I₃ are unit metrices of order 2 and 3 where
I₂ = 1 0 and I₃= 1 0 0
0 1 0 1 0
0 0 1
NOTE:
1) All the diagonal elements of the unit matrix should be + 1 only.
2) The diagonal matrix, scalar matrix and unit matrix all the square matrices i.e., in each of them the number of rows= the number of columns.
g) UPPER TRIANGULAR MATRIX:
This is a square matrix whose each element below the princpal diagonal is zero. Example
1) 2 3 2) 2 4 0 3) 2 0 0
0 1 0 3 1 0 0 1
0 0 5 0 0 5
h) LOWER TRIANGULAR MATRIX:
This is a square matrix whose elements above the principle diagonal is zero. Example.
1) 2 0 2) 2 0 0 3) 0 0 0
1 3 3 1 0 2 0 0
4 0 1 3 1 0
****************"*"*********""""***********
* ADDITION OF TWO MATRICES *
Two matrices can be added or subtracted only if they are of the same order and this is done by adding or subtracting the corresponding elements of two matrices.
PROPERTIES OF MATRIX ADDITION:
1) A+ B= B + A
2) A +(B+C)= (A+B)+C
3) A + O= O +A = A
Where A, B, C are the matrices of the same order and O is the null matrix of the same order.
1) If A= 2 5 and B= 1 -3
-3 7 2 5
Find A+ B. 3 2
-1 12
2) If A= 3 -6 & B= 1 -3
9 3 3 0
find 2A+ B. 7 -15
21 6
3) If A= 2 -3 and B= -1 6
4 5 3 2
Find 2A+ 5B. -1 24
23 20
4) If M= 2 0 and N= 2 0
1 2 -1 2
Find M+ 2N. 6 0
-1 6
5) If A= 2 0 and B= 1 2
-3 1 3 1
Find 3A+ 4B. 10 8
3 7
6) If A= 1 4 and B= -4 -1
2 3 -3 -2
Find 2A+ B. -2 7
1 4
7) If A= 2 4 and B= 1 3
3 2 -2 5
Find 2A+ 3B. 7 17
0 19
8) If A = -3 5 and B= 2 -3
-9 11 6 7
find 2A + 3B. 0 1
0 1
9) If A= -3 2 1 & B= 3 5 1
1 -4 7 -1 4 -2 find A+ B. 0 7 2
0 0 5
10) If A= diag(1 -1 2) and B= diag(2 3 -1), find
A) A+ B. diag (3 2 1)
B) 3A + 4B. diag(11 9 2)
11) If M= 2 0 and N= 2 0
1 2 -1 2 find
M +N. 4 0
0 4
Exercise - B
1) If A= 3 -1 7 & B= 2 -2 -1
0 1 2 1 2 3
Find A+ B. 5 -3 6
1 3 5
If A= 2 1 & B= 0 0 2 1
4 -2 0 0 4 -2
Find A+ B. 3 -1
2 1
4 -2
4) if A = 1 2 3 B= 4 -2 -2
0 3 - 5 6 2 -1
1 0 0 1 -2 3
find 2A + 3B. 14 -2 0
18 12 -13
5 -6 9
5) 1 2 3 3 -1 3
A= 2 3 1 & B = -1 0 2
Find 2A + 3B. 5 1 15
1 6 5
6) A= 2 3 4 & B= 3 0 5
0 4 6 5 3 2
5 8 9 0 4 7 find 3A - 2B. 0 9 2
-10 6 14
15 16 13
7) A=1 -3 2 B= 2 -1 -1 C= -3 4 -1
2 0 2 1 0 -1 -3 0 -1
Find 2A + 3B+ C
8) If A=1 3 5 and B= 4 2 3
0 4 1 1 3 -7
Verify 2(A+B)= 2A +2B
* SUBSTRACTION OF MATRICES *
If A and B are metrices of the same order, then A - B = A+ (-1)B. Hence if A= [aᵢⱼ]ᵤₓᵥ and B= [bᵢⱼ]ᵤₓᵥ then
A - B = [aᵢⱼ]ᵤₓᵥ + (-1) [bᵢⱼ]ᵤₓᵥ
= [aᵢⱼ - bᵢⱼ]ᵤₓᵥ
Thus A - B is a matrix of the same order of matrix A and B, whose elements are the members obtained from substracting the corresponding elements of B from A. for example, if
A= x₁ y₁ z₁ a₁ b₁ c₁
x₂ y₂ z₂ and B= a₂ b₂ c₂
x₃ y₃ z₃ a₃ b₃ c₃
then,
A - B= x₁- a₁ y₁-b₁ z₁ - c₁
x₂ -a₂ y₂- b₂ z₂ -c₂
x₃ -a₃ y₃ -b₃ z₃ -c₃
NOTE:
1) Since - A= (-1)A = (-1) [aᵢⱼ]ᵤₓᵥ i.e., all the elements of A with sign changed, hence - A is called the negative matrix of matrix A.
Again, since A +(- A)= (- A)+ A=0, so - A is called the additive inverse of A.
2) If A + B = A + C, or
B + A = C + A, then B = C, where A, B, C are matrices of same order.
Exercise - C
** EQUALITY OF TWO MATRICES:
Two matrices are said to be equal if
1) they are of same orders.
2) each element of one is equal to the corresponding element of the other. For example, if A and B are matrices both of order 2x 3 and
A = a b c and B = p q r
d e f x y z
Then A= B implies a= p, b= q, c= r, d= x, e= y, and f= z.
1) x 7 + 6 -7 = 20 7
9 y-5 4 5 22 15
find x and y. 14, 22
2) a 3 + 2 1 - 1 b = 5 0
4 2 1 -2 -2 c 7 3
find a, b, c. 4, -1,3
3) If A= 2a - b 4 = 2 4
3 a+2b 3 6 find the value of a and b. 2,2
4) If x+y 2 = 6 2
5 xy 5 8 find the value of x and y. 2, 4 or 4, 2
5) If A=2 a B = -2 3 C = c 9
-3 5 7 b -1 -11
and 5A + 2B = C find a, b, c. 6/5, -18,6
6) If A= x y B= 1 -1 & C= 3 5
z t 0 2 4 6 with the relation 2A+ 3B = 5C then find the value of x,y,z and t. 6,14,10,12
14) If X + Y = 7 0 and X - Y= 4 -1
2 3 5 -2
find metrices X And Y.
11/2 -1/2 3/2 1/2
7/2 1/2 -3/2 5/2
15) A+ B= 2 2 2A+ 3B= 5 4
0 2 and 0 5 then find the Matrix A and B.
1 2 1 0
0 1 0 1
16) If A+B= 1 2 0 A - B= 3 0 2
3 5 4 1 1 0
Find the metrices A and B
2 1 1 -1 1 -1
2 3 2 1 2 2
17) If A+B= 2 2 and A - B= 5 4
0 2 0 5
Find the metrices A and B.
7/2 3 -3/2 -1
0 7 0 -3/2
18) If 2P + Q= 4 5 & P + 2Q= 2 4
3 8 3 1 Then find the value of P+ Q. 2 3
2 3
19) If 2A+ B= 4 4 7 & A- 2B = -3 2 1
7 3 4 1 -1 2 find the Matrix A and B
1 2 3 2 0 1
3 1 2 1 1 0
20) If 2x -y= 6 -6 0 & x +2y =3 2 5
-4 2 1 -2 1 -7 find the Matrix x and y. 3 -2 1 0 2 2
-2 1 -2 0 0 -3
21) If 2A+B= 4 7 16
7 -3 12
. 13 6 2
And 3B - A= 5 0 13
7 -2 8
11 4 -1
Find metrices A and B
2 1 6 1 3 5
3 -1 4 2 -1 4
5 2 0 4 2 1
22) If A + 2B = 1 2 0
6 -3 3
-5 3 1
and 2A - B= 2 -1 5
2 -1 6
0 1 2
Find metrices A and B.
0 5/3 -5/3 1 1/3 10/4
10/3 -5/3 0 -2/3 1/3 3
-10/3 5/3 0 5/4 -1/3 1
23) X - y = 1 1 0 and x+ y= 3 5 1
1 1 0 -1 1 4
1 0 0 11 8 9 find Matrix x and y. 2 3 1 1 2 0
0 1 2 -1 0 2
6 4 0 5 4 0
1) If A = 1 3 B = 4 -5
2 -2 3 -1 Find
i) AB. 13 -8
2 -12
ii) BA. -6 22
1 11
iii) A². 7 -3
-2 10
iv) (AB)². 153 8
2 128
v) A² - B². 6 12
-11 24
vi) A² - 2B. -1 7
-8 12
2) If A = 1 2 B= 3 4 C= -1 0
5 -4 0 2 2 -2
find i) ABC
ii) (A+B)C
iii) A² - BC
iv) AC + B²
v) (A+ B) (A - B)
vi) AC + B²
6) If A = 1 2 3 and B = 6 -2 -3
1 3 3 -1 1 0
-1 0 1 1 2 4
evaluate AB , BA
7) If A = 1 -2 1
-1 2 -1 show A² = A
-2 4 -2
8) If A= 1 -1 and B= 1 1
-1 1 1 1
prove AB=0.
9) If A = 1 2 1 & B= 1 4 0
1 -1 1 -1 2 2
2 3 1 0 0 2
Find AB - 2B
10) If A= 3 2. 5 B= 1 2 & C= 7 - 8
2 -4 0 2 -1 5 Find AB - C
11) If A= 0 1 2 B = 2 1 3
1 2 3 -1 0 1
3 1 1 3 -1 4
Verify AB≠ BA
12) If A = 1 2 3 and B= 6 -2 -3
1 3 3 -1 1 0
1 2 4 -1 0 1
Check AB = BA
13) If A=2 -3 -5 and B= -1 3 5
-2 4 5 1 -3 -5
1 -3 -4 -1 3 5
Prove AB≠BA
14) If A= 1 & B= 1 2 3 find BA
2
3
15) If A is 3 -2 0 & B= 2 find BA
0
3
16) If A= 2 3 -1 B= 1 & C= 1 -2
3 0 2 1
2
Verify A(BC)≠ (AB)C
17) if A= 0 1 0 & B = 0 0 1
0 0 1 1 0 0
1 0 0 0 1 0
verify i) A²= B ii) B² = A
18) If A= 2 -1
- 1 2 show that A²- 4A+ 3I = 0, where I is 2 x2 unit Matrix and 0 is 2x2 zero Matrix.
19) If I= 1 0 & B= 3 2
0 1 2 1 show that A²- 4A - I= 0, where 0 is the zero Matrix of order 2
20) If A= 4 3 and B= 1 0
2 5 0 1 find the values of x and y so that A² - xA + yI =0, where 0 is the zero Matrix of order 2. 9, 14
21) If A = 2 -1 show A² - 4A + 3I =0
-1 2
22) If A = 2 0 1 find A² - 5A + 6I
2 1 3
1 -1 0
23) If A = a b
c d
show A² - (a+d)A+(ad-bc) I=0
24) for what values if x,y,z If A .A = I′ &
A= 0 2y z
x y -z
x -y z
25) A= 1 -1 and B = 1 x
2 -1 4 y and
(A +B)² = A² + B² then find x,y.
26) if A= 6 5 & C= 11 0
MATRIX NOTATION:
A₂ ₓ ₃ = a₁₁ a₁₂ a₁₃
a₂₁ a₂₂ a₂₃
The above notation means that A is a matrix having two rows and three columns. a₁₁ is the element situated at the junction of 1st row and 2nd Column, a₂₃ is the element situated at the junction of 2nd row and 3rd Column, etc.
Example Let B₃ₓ₂ = 4 -1
0 2
1 4
then b₁₁ = 4, b₁₂ = -1, b₂₁=0, b₂₂= 2,
b₃₁ = 1, b₃₂= 4.
NOTE : A matrix A having m rows and n columns is also denoted (aᵢⱼ)ᵤₓₙ .
Example:
Construct a 2x 2 matrix A = (aᵢⱼ) whose elements are given by aᵢⱼ=(1+2j)²/2
Solution)
A= a₁₁ a₁₂
a₂₁ a₂₂
Where, a₁₁= (1+2x1)²/2= 9/2
a₁₂ = (1+2x2)²/2 = 25/2
a₂₁ = (2+ 2x1)²/2= 8
a₂₂ = (2+ 2x2)²/2= 18
So required matrix A= 9/2 25/2
8 18
1) construct a 2 x 2 matrix A = [aᵢⱼ] whose elements are given by
A) aᵢⱼ = (i+j)²/2. 2 9/2
9/2 8
B) aᵢⱼ = (i -j)²/2. 0 1/2
1/2 0
C) aᵢⱼ= (i- 2j)²/2. 1/2 9/2
0 2
D) aᵢⱼ= (2i-j)/2. 1/2 0
3/2 1
E) aᵢⱼ= |2i -3j)|/2. 1/2 2
1/2 1
F) aᵢⱼ= |-3i+ j|/2. 1 1/2
5/2 2
2) construct a 2x2 Matrix A = [aᵢⱼ] whose elements are given by aᵢⱼ= (i - j)/(i + j).
0 -1/3
1/3 0
3) Construct a 2x3 Matrix whose elements aᵢⱼ are given by:
A) aᵢⱼ= i. j. 1 2 3
2 4 6
B) aᵢⱼ= 2i - j. 1 0 -2
3 2 1
C) aᵢⱼ= i+ j. 2 3 4
3 4 5
4) Construct a 2x2 Matrix whose elements aᵢⱼ are given by:
A) (i+j)²/2. 2 9/2
9/2 8
B) (i -j)²/2. 0 1/2
1/2 0
C) (2i+j)²/2. 9/2 8
25/2 18
D) aᵢⱼ= |-3i+ j|/2. 1 1/2
5/2 2
5) Construct a 2x3 matrix A= [aᵢⱼ] whose elements are given by
A) aᵢⱼ= (i - j)/(i+j). 0 -1/3 -1/2
1/3 0 -1/5
B) aᵢⱼ= i. j. 1 2 3
2 4 6
C) aᵢⱼ = 2i - j. 1 0 -1
3 2 1
D) aᵢⱼ = i +j. 2 3 4
3 4 5
E) aᵢⱼ = (i+j)²/2. 2 9/2 8
9/2 8 25/2
6) Construct a 3x4 matrix A= [aᵢⱼ] whose elements aᵢⱼ are given by:
A) aᵢⱼ= i+ j. 2 3 4 5
3 4 5 6
4 5 6 7
B) aᵢⱼ= i - j . 0 -1 -2 -3
1 0 -1 -2
2 1 0 -1
C) aᵢⱼ= 2i. 2 2 2 2
4 4 4 4
6 6 6 6
D) aᵢⱼ= j. 1 2 3 4
1 2 3 4
1 2 3 4
E) aᵢⱼ = 1/2 |-3i+j|. 1 1/2 0 1/2
5/2 2 3/2 1
4 7/2 3 5/2
7) Construct a 4x3 matrix elements
A) aᵢⱼ= 2i + i/j. 3. 5/2. 7/3
6 5 14/3
9 15/2 7
12 10 28/3
B) aᵢⱼ=(i-j)/(i+j). 0 -1/3 -1/2
1/3 0 -1/5
1/2 1/5 0
3/5 1/3. 1/7
Exercise - H
1)If A = 2. 4 -1 and B = 3 4
-1 0 2 -1 2
2 1
Find
i) A′
ii) A′ +B′
iii) (A - B)ᵗ
iv) (AB)′
v) Aᵗ Bᵗ
2) If A= 2 1 and B= 1 -2
3 4 -1 1
Prove (AB)'= B ' A '
3) If A = 0 -1
2 3
Prove (A ')' = A
4) If A = 4 2 -1 and B= 2 3
3 -7 2 -3 0
1 5
Find possible or not A+B, A - B , AB, BA
5) Let A= 2 -3 & B= 1 0
-7 5 2 -4 Verify
A) (2A)'= 2A'
B) (A+ B)'= A' + B'
C) (A - B)'= A' - B'D) (AB)' = B' A'
6) Let A=1 -1 0 & B= 1 2 3
2 1 3 2 1 3
1 2 1 0 1 1 verify
A) (A+ B)'= A'+ B'
B) (AB)'= B' A'
C) (2A)'= 2A'
7) If A= 2 1 3 & B= 1 -1
4 1 0 0 2
5 0 verify
(AB)'= B' A'
Exercise - I
** A square Matrix A is a symmetric Matrix iff A'= A
** A square Matrix A is a skew-symmetric Matrix iff A'= - A
*** Sum of a symmetric and skew-symmetric Matrix= 1/2 (A+ A')+ 1/2 (A - A')
1) If A= 3 -1 1
-1 2 5
1 5 -2 is a symmetric Matrix.
2) if A= 0 2 -3
-2 0 5
3 -5 0 is a skew-symmetric Matrix.
3) If A= 2 3
4 5 Prove A- A' is a skew-symmetric Matrix
4) if A= 3 -4
1 -1 show that A - A' is a skew-symmetric Matrix.
5) If A= 5 2 x
y z -3
4 t -7 is a symmetric Matrix, find x,y z, t. 4, 2 , -3
6) Express the Matrix A as the sum of symmetric and skew-symmetric Matrix
A= 4 2 -1
3 5 7
1 -2 1
7) Express the Matrix A as the sum of symmetric and skew-symmetric Matrix
A= 3 -4
1 -1
8) Let A= 3 2 7
1 4 3
2 5 7 Find matrix X and Y such that X+Y = A, where X is a symmetric and Y is a skew-symmetric matrix.
9) If A= 2 4
5 6 Prove A+A' is a symmetric matrix where A' is the transpose of A.
EXERCISE -J
Find the determinants of
EXERCISE - L
Find the adjoint of the following:
1) a b d -b
c d -c a
2) -3 5 4 -5
2 4 -2 -3
3) p q s -q
r s -r p
4) - 2 3 4 -3
- 5 4 5 -2
5) 1 -3 1 3
2 1 -2 1
6) cosx sinx cosx - sinx
sinx cosx -sinx cosx
7) 1 tan(x/2) 1 -tan(x/2)
- tan(x/2) 1 tan(x/2) 1
8) 1 2 2 -3 2 2
2 1 2 2 -3 2
2 2 1 2 2 -3
9) 1 2 5 2 3 -13
2 3 1 -3 6 9
-1 1 1 5 -3 -1
10) 2 -1 3 -22 11 -11
4 2 5 4 -2 2
0 4 -1 16 -8 8
11) 2 0 -1 3 -1 1
5 1 0 -15 7 -5
1 1 3 4 -2 2
12) cosx - sinx 0 cosx sinx 0
sinx cosx 0 -sinx cosx 0
0 0 1 0 0 1
13) 1 1 1 9 -1 4
2 1 -3 -3 4 5
-1 2 3 5 -3 -1
14) 2 -1 3 -22 11 -11
4 2 5 4 -2 2
0 4 -1 16 -8 8
15) -6 0 3 7 -15 -3
-2 1 1 0 0 0
-4 -5 2 14 -30 -6
16) -4 -3 -3
If A= 1 0 1
4 4 3
Show that adj A= A
17) 1 -2 3
If A= 0 2 -1
-4 5 2
Find A(adj). 25 0 0
0 25 0
0 0 25
EXERCISE - M
State which of the following are INVERTIBLE :
1) 2 -3
2 3 YES
2) 4 -1
-4 1. NO
3) 5 2 -3
4 -5 2 NO
0 3 -2
4) 1 1 -1
2 3 1. YES.
1 -1 -2
*** FIND the condition for which the following matrices are INVERTIBLE
1) a b
c d ad-bc≠ 0
2) sinx cosx
-sinx cosx (0≤0≤π/2). 0≠0,π/2
Find the inverse of following:
1) 2 -1 4/11 1/11
3 4 -3/11 2/11
3) cosx sinx cosx -sinx
-sinx cosx sinx cosx
4) 0 1 0 1
1 0 1 0
5) a b (1+bc)/a -b
c. (1+bc)/a - c a
6) 2 5 1/17 -5/17
-3 1 3/17 2/17
7) 1 tanx cos²x sinx cos
EXERCISE -N
Prove that
1) a) A=2 3
5 -2 then A⁻¹ = A/19
2) if A=. 4 5
2 1 Verify A= 5I +6A⁻¹
3) show A = 2 -1 and B = 2
4 3 -3
and AX = B Find the matrix X.
4) If A= 1 -2 & B= 6 0
1 4 0 6 Find the Matrix C If CA = B. 4 2
-1 1
5) If A= 2 1 B= -3 2 & C= 1 0
3 2 5 -3 0 1 find Matrix X if AXB= C. 1 1
1 0
6) If A= 1 -4 B= -16 -6
3 -2 7 2 find the Matrix X if AX= B. 6 2
11/2 2
7) A= 5 4 & B= 1 -2
1 1 1 3 find the Matrix X as the relation AX = B. -3 -14
4 17
8) If A= 3 2 B= -1 1 & C= 2 -1
7 5 -2 1 0 4 find the Matrix X as AXB= C. -16 3
24 -5
9) If A= 5 3 & B= 14 7
-1 -2 7 7 find the Matrix X as XA= B. 3 1
1 -2
10) if A= 2 -1
-1 2
satisfies the relation A² - 4A + 3I =0 hence find A⁻¹
11) If A = 1 1
2 3
prove A² - 4A +5I=0. Hence find A⁻¹.
3/5 1/5
-2/5 1/5
12) If A = 4 5 satisfies A² - I=10A
5 6 Hence find A⁻¹
13) A= 2 -3
3 4 satisfies the equation x²- 6x+17= 0. Hence find A⁻¹. 4/17 3/17
-3/17 2/17
14) If A= 3 22 1 2 and, Hence find A⁻¹
2 2 1 3/5 2/5 2/5
2/5 -3/5 2/5
2/5 2/5 -3/5
22) IfA= 2 2 0 then A³-13A+12I=0
2 1 1 . Hence find A⁻¹
-7 2 -3
23) A= 1 2 3
3 -2 1 show A³ -23A-40I=0
4 2 1 Hence find A⁻¹
24) If A= 1 0 -2
-2 -1 2
3 4 1 Show that A³- A²- 3A - I = O. Hence find A⁻¹. -9 -8 -2
8 7 2
-5 -4 -1
25) If A = 1 0 -2
2 2 4
0 0 2
Find A² - 3A + 2I where I= 3x3 then find Inverse of A.
EXERCISE -O
Find the inverse of each of the following matrices by using elementary row transformation:
A)
1) 5 2 1 -2
2 1 -2 5
2) 1 6 5/23 -6/23
-3 5 3/23 1/23
3) 7 1 3/25 1/25
4 -3 4/25 -7/25
4) 3 10 7 -10
2 7 -2 3
B)
1) 0 1 2 1/2 -1/2 1/2
1 2 3 -4 3 -1
3 1 1 5/3 -3/2 1/2
2) 2 0 1 3 -1 1
5 1 0 -15 6 -5
0 1 3 5 -2 2
3) 2 3 1 1 1 -1
2 4 1 -1 1 0
3 7 2 2 -5 2
4) 3 -3 4 1 -1 0
2 -3 4 -2 3 -4
0 -1 1 -2 3 -3
5) 2 -1 4 -2 1/2 1
4 0 2 11 -1/2 -2
3 -2 7 4 -1/2 -2
EXERCISE - P
Solve:
1)
A) 5x - 7y =2, 7x - 5y =3,. 11/24, 1/24
B) x - 2y -4 =0, -3x +5y+7 =0, -6,-5
C) 3x+ 4y =5, x-y =-3. -1,2
D) ax+ by=c, a²x +b²y =c².
E) 3/x - 5/y =1 , 2/x +3/y = 7.
F) a/x -b/y =a , a/y - b/x =b.
G) 5x +7y =-2, 4x +6y+3=0. 9/2,-7/2
H) 5x +2y =3, 3x +2y=5. -1,4
I) 3x +7y =4, x +2y+1=0. -15,7
2)
A) x+y-z=3, 2x+3y+z=5 , 3x-y-7z=1. 3,1,1
B) x+ 2y+z=7; x+ 3z=11; 2x-3y=1. 2,1,3
C) 2y-3z=0, x+3y= -4, 3x+4y =3
E) x+y-6z=0, -3x+y+2z=0, x-y+2z=0
F) x+y+z=4, 2x-y+2z=5 , x-2y-z=-3
F) (a+b)x - (a-b)y= 4ab,
(a-b)x + (a+b)y = 2(a² -b²)
G) 1/x +2/y+ 3/z=2
2/x +4/y +5/z =3
3/x +5/y+6/z= 4
H) 2/x +3/y +2=0
5/y - 2/z -4 =0
3/z +4/x +7=0
Continue.......