Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Exercise 2.3>Q 2

MEDIUM

12th Maharashtra Board

IMPORTANT

Earn 100

Solve the following equations by the reduction method.

$3 x - y = 1$ , $4 x + y = 6$

Important Questions on Matrices

MEDIUM

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Exercise 2.3>Q 2

Solve the following equations by the reduction method.

$5 x + 2 y = 4$ , $7 x + 3 y = 5$

HARD

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Exercise 2.3>Q 3

The cost of

4

pencils,

3

pens and

2

erasers is

₹ 60

. The cost of

2

pencils,

4

pens and 6 erasers is

₹ 90

, whereas the cost of

6

pencils,

2

pens and 3 erasers is

₹ 70

. Find the cost of each item by using matrices.

HARD

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Exercise 2.3>Q 4

If three numbers are added, their sum is '

2

'. If

2

times the second number is subtracted from the sum of first and third number we get '

8

' and if three times the first number is added to the sum of second and third number we get '

4

'. Find the numbers using matrices.

MEDIUM

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Exercise 2.3>Q 5

The total cost of

3

televisions and

2 V . C . R . s

is

₹ 35000 .

The shop-keeper wants profit of

₹ 1000

per television and

₹ 500

per

V . C . R .

He can sell

2

televisions and

1 V . C . R .

and he gets the total revenue as

₹ 21, 500 .

Find the cost and the selling price of a television and a

V . C . R .

HARD

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Miscellaneous Exercise 2(B)>Q 1

Choose the correct alternative.
If

A = [\begin{array}{l} 1 & 2 \\ 3 & 4 \end{array}], a d j A = [\begin{matrix} 4 & a \\ - 3 & b \end{matrix}]

then the values of

a

and

b

are,

MEDIUM

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Miscellaneous Exercise 2(B)>Q 2

The inverse of

[\begin{matrix} 0 & 1 \\ 1 & 0 \end{matrix}]

is

HARD

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Miscellaneous Exercise 2(B)>Q 3

If

A = [\begin{array}{l} 1 & 2 \\ 2 & 1 \end{array}]

and

A (adj A) = k I

then the value of

k

is _____

HARD

12th Maharashtra Board

IMPORTANT

Mathematics & Statistics (Arts & Science) Part 1 Standard 12>Chapter 2 - Matrices>Miscellaneous Exercise 2(B)>Q 4

If

A = [\begin{matrix} 2 & - 4 \\ 3 & 1 \end{matrix}]

then the adjoint of matrix

A

is