Download Practice Paper Class XII CHEMISTRY Q1State the magnetic

Kendriya Vidyalaya Sector-8 R K Puram(2nd Shift)
Summer Vacation Homework
Class – XII
ECONOMICS
1.) A consumer consumes only two goods. Explain equilibrium with the help of utility
approach.
2.) Explain consumer’s equilibrium with the help of indifference curve analysis.
3.) A consumer consumes good ‘X’ Explain the effects of fall in the prices of related goods
on the demand of ‘X’ . Use diagram showing demand for good X on the X-axis and its
price on Y-axis.
4.) Distinguish detween change in demand and change in quantity demanded.
5.) A 3% fall in the price of X leads to a 9% rise in its demand . A 5% rise in the price of Y
leads to a 5% fall in its’s demand. Calculate the price elasticity of demand for X and Y .
Which one is more elastic?
6.) When price of a good falls from Rs 15 per unit to Rs 12 per unit , it’s demand rises by
25%. Calculate price elasticity of demand.
7.) Price elasticity of demand for a commodity is unity and a household demands Rs 50 units
of it when it’s price is Rs2 per unit. At what price will the household demands 45 units of
the commodity?
8.) Explain ,in brief, the following kinds of price elasticities of demand, (i) Highly elastic
demand, (ii) Unitary elastic demand, (iii) Less elastic demand.
9.) Explain the various factors that affects elasticity of demand.
10) Explain the significance of elasticity of demand.
Physics
A. Preparation of Innovative exhibit with write ups for Science Exhibition.
B. Self study of following chapters and follow up exam of 35 marks in month of June.
Unit -5 ( EMW), Unit – 6 (ray optics & optical instruments), unit – 8 (Atoms &
Nuclei)
C. Solve following assignment in HW copy
Q1. . An electric dipole is held in a uniform electric field (i) using suitable diagram show that it
does not undergo any translatory motion and (ii) drive an expression for the torque acting on it
and specify its direction.
Q2. State Gauss’s theorem & apply this theorem to obtain an expression for the electric field
intensity at a point due to (i)an infinitely long uniformly charged straight wire (ii) a uniformly
charged infinite sheet (iii) a uniformly charged thin spherical shell at an (a) outside point (b)
inside point.
Q3. (a)Deduce an expression for the capacitance of a parallel plate capacitor with air as the
medium between the plates (b)A dielectric slab of thickness‘t’ is kept in between the plates each
of area A of parallel plate capacitor separated by a distance of‘d’. Drive an expression for the
capacitance of capacitor for t <<d.
Q4. (i) Explain briefly how a capacitor stores energy on charging. Obtain expression for energy
stored (ii) A parallel plate capacitor of plate separation’s’ is charged to a p.d. ‘V’. A dielectric
slab of thickness d and dielectric constant K is introduced between the plates while the battery
remains connected to the plates.
(a) Find the ratio of energy stored in the capacitor after and before the dielectric in
introduced, give physical explanation for this change in stored energy.
(b) What happens to the charge on the capacitor?
(c)How does the electric field between plates change.
Q5. In a Van de Graaff type generator a spherical metal shell is to be a 15 × 106 V electrode. The
dielectric strength of the gas surrounding the electrode is 5 × 107 Vm–1. What is the minimum
radius of the spherical shell required? (You will learn from this exercise why one cannot build an
electrostatic generator using a very small shell which requires a small charge to acquire a high
potential.) [Ans 30cm]
Q6. A parallel plate capacitor with air as dielectric is connected to a power supply and charged to
a potential difference Vo. After disconnecting from power supply, a sheet of insulating material
is inserted between the plates completely filling the space between them. How will its (i) charge
on the plates (ii) electric field between the plates (iii) potential difference between the plates (iv)
capacitance (v) energy stored in the capacitor. Q7. (a) Describe the formula for the equivalent
EMF and internal resistance for the parallel combination of two cells with EMF E1 and E and
internal resistances r1 and r2 respectively. (a)What is the corresponding formula for the series
combination?
(b) Two cells of EMF 1V, 2V and internal resistances r2 and r1 respectively are connected in (i)
series, (ii) parallel. What should be the external resistance in the circuit so that the current
through the resistance be the same in the two cases? In which case more heat is nerated in the
cells?
Q8. Deduce the condition for balance in a Wheatstone bridge. Using the principle of
Wheatstone bridge, describe the method to determine the specific resistance of a wire in the
laboratory. Draw the circuit diagram and write the formula used. Write any two
precautions.
Q9. Describe the principle and construction of potentiometer.
Explain how a potentiometer can be used to compare the emfs of
two primary cells?
Q 10. Draw Circuit diagram for a meter bridge to determine the
unknown resistance of a
resistor. Obtain the balance condition for a meter bridge. Find the
shift in the balance
point for a meter bridge when two resistors in its two gaps, are
interchanged.
Q 11. Are the paths of e’s straight lines between successive
collisions in the (i) absence of electric field (ii) presence of electric field. Establish a relation
between drift velocity and current. Hence obtain the relation between current density and drift
velocity.
Q12. With the help of a neat and labeled diagram, explain the underlying principle and working
of a moving coil galvanometer. What is the function of (i) uniform radial field (ii) Soft iron core?
.
Q13. Using Kirchoff’s laws, calculate the potential difference across the 8 ohm resistor.
[Ans : Current through resistance 8
= 0.46A, P. d. = 3.68Volts]
Q14. E2 =1.02V, PQ=1m.When switch S open, null position is obtained at a distance of 51 cm
from P. Calculate (i) potential gradient (ii) emf of the cell E1 (iii) when
switch S is closed, will null point move towards P or Q. Give reason for
your answer.
[Ans: (i) Potential gradient k = 0.02V/cm (ii) emf of the cell E1 = 2V
(iii) When switch S is closed, null point is not affected because no
current drawn from cell E1 at the null point. ]
Q15. In the potentiometer circuit shown, the balance point is at X. State
with reason, where the balance point will be shifted
when (i) R is increased; (ii) S is increased, keeping R
constant. (ii) Cell P is replaced by another cell whose
emf is lower than that of cell Q.
Q16. Two identical plane metallic surfaces A and B
are kept parallel to each other in air separated by a distance
of 1 cm as shown in figure.
A is given a positive potential of 10V and the outer surface
of B is earthed. (i) What is the magnitude and direction of
the uniform electric field between Y and Z? (ii) What is
the work done in moving a charge of 20 C from X to Y?
Ans : (i) E = 1000 V/m, direction from A to B
(ii) Zero.
Q17. The following data was obtained for the dependence of the magnitude of electric field, with
distance, from a reference point O, within the charge distribution in the shaded region.
B
C
A’
B’
C’
Field Point A
Magnitude
E
E/8
E/27
E/2
E/16
E/54
of electric
field
(i) Identify the charge distribution and justify your answer.
(ii) If the potential due to this charge distribution, has a value V
at the point A, what is its value at the point A’?
Q18. Use Gauss’s law to obtain an expression for the electric
field due to an infinitely long straight uniformly charged wire.
Electric field in the above figure is directed along + X direction
and given by Ex = 5Ax + 2B, where E is in NC-1 and x is in
metre, A and B are constants with dimensions
Talking A=10NC-1m-1 and B = 5NC-1 calculate. (i) the electric
flux through the cube. (ii) net charge enclosed within the cube.
[Ans (i ) 0.05Nm2/C (ii) 44.25X10-14C ]
Q19. Two point charges of charge values Q and q are placed at
distance x and x/2 respectively from a third charge of charge
value 4q, all charges being in the same straight line. Calculate the
magnitude and nature of charge Q such that the net force
experienced by the charge q is
zero. [Ans Q = q/4 , +ive ]
Q20Total capacitance of the combination between A and B in the given figure is 15μF. Calculate
the capacitance of capacitor C.
[ Ans. 60 μF]
Q21. On charging a parallel plate capacitor to a potential V, the spacing between the plates is
halved, and a dielectric medium of r
= 10 is introduced between the plates, without
disconnecting the d.c source. Explain using suitable expressions, how the (i) capacitance (ii)
electric field (iii) energy density of the capacitor change.
[Ans(i) C1= 20Co (ii) E 1=2Eo (iii) u1 = 40uo ]
POLITICAL SCIENCE
1. Solve your monthly test question paper in your note book.
2. Chapter for self study is end of Bipolarity.
3. Answer all these questions in your note book.
THE COLD WAR ERA
1. What is meant by "Arenas of cold war"?
2. Why did India not join either of the two camps during the cold war?
3. Mention military alliances which were set up after the Second World War.
4. Name any two factors of Non-Aligned Movement (NAM). The first NAM Summit was
the culmination of which three factors.
5. Assess India's role in strengthening the Non-Aligned Movement.
6. What is the relevance of the Non-Aligned Movement after the end of cold war? Explain.
7. What is meant by New International Economic Order? Mention any four reforms of the
Global Trade System proposed by UNCTAD in 1972.
8. Write a short note on following:
i.
Limited Test Ban Treaty
ii.
Nuclear Non-Proliferation Treaty
iii. Strategic Arms Limitation Talks (I)
iv.
Strategic Arms Limitation Talks (II)
1.
2.
3.
4.
5.
1.
2.
3.
4.
CHALLENGES OF NATION BUILDING
Who was the first Indian to be Governor General of India? He founded which party in
1959?
Who was Potty Sriramulu? What was the outcome of his indefinite fast?
Explain the circumstances that compelled the union government to announce the
formation of a separate Andhra state in December 1952.
Mention the role of Sardar Vallabhbhai Patel towards India's integration.
Describe briefly any four problem faced in the process of partition of India.
ERA OF ONE-PARTY DOMINANCE
Analyse the reason for the dominance of Congress party in the first three general
elections.
Explain how the General Election of 1952 in India were a landmarks in the history of
democracy all over the world.
Write a short note on Communist Victory in Kerala in 1957.
During the early years of Independence, despite the fact that the opposition parties had
token representation they played a crucial role in maintaining the democratic character of
the system. How?
BUSINESS STUDIES
1 Make a project file either on;
Principles of management
Elements of business environment
2 make notes on chapter 1 to 4
3 learn all chapters 1 to 4
4 write atleast 5 multidisciplinary questions and answers from chapter 1 to 4
5 write 5 hots and value based questions answers from each chapter done.
ACCOUNTANCY
1 Make a comprehensive project
2 complete exercise of book from chapter 1 to 4
3 make 5 short theory question answer fromeach chapter done
4 revise all chapters till admission of a partner.
Subject:Biology.
1. Answer all the questions of lesson 1to 4 in H.W copy.
2. Complete the assigned work in practical file.
3. Select any suitable application based project and collect
information related to it and chalk out its experimentation ect.
4. Read carefully the following lessons and frame 2,3 5 marks
questions.(10 questions of 2 marks,10 of 3 marks and 3 of 5
marks.)
EVOLUTION
ORGANISM AND POPULATION
BIODIVERSITY
ENVIRONMENTAL POLLUTION
5.Paste question paper of monthly test of MAY in C.W copy and answer all
the questions.
English Core
Q1. (a) Read at least two short reports in any English newspaper. Cut and paste them on your
note-book. On the basis of your reading of these reports, make notes on them in points only,
using headings and sub-headings. Use recognizable abbreviations wherever necessary.
(b) Make a summary of these passages in not more than 80 words and also suggest a suitable
title.
Q2. You have cleared Medical Entrance Examination. The family is elated at this achievement
and they decide to have a get-together for all friends. Draft an informal invitation for the gettogether.
Q3. You want to sell car as you are going abroad. Draft a suitable advertisement to be published
in a national daily.
Q4. Water is precious and each one of us must stop wastage. Design a poster in not more than 50
words urging people to employ various methods of rain water harvesting in their colonies.
Q5. You lost your bus pass in the school. Write a notice in not more than 50 words giving details
of the pass and the probable time of the day you lost it.
Q6. Your school organized a ten day camp in a village during the summer holidays. As the
leader of team, write a letter to the editor of a newspaper giving an account of your activities
there.
Q7. Stefani of 15-A, C.P. Road, New Delhi desires to be a fashion designer. She writes to the
Director of the National Institute of fashion Technology, Bangalore, seeking information about
their courses, admission procedure, eligibility criteria, fee structure, placement opportunities etc.
Write her letter.
Q8. In spite of the advancement in technology, luxuries and freedom, the new generation is a
worried lot. Write an article in about 100 words giving your views on this. You are
Kartik/kritika.
Q9. Describe the dramatic entry of the stranger at the Coach and Horses and his strange
behaviour.
10. Describe the meeting between Marvel and the Invisible Man.
Computer Science
1. What will be the output of the following program:
#include <iostream.h>
void Secret(char Str[ ])
{
for (int L=0;Str[L]!='\0';L++);
for (int C=0;C<L/2;C++)
if (Str[C]=='A' || Str[C]=='E')
Str[C]=Str[L-C-1];
else
{
char Temp=Str[C];
Str[C]=Str[L-C-1];
Str[L-C-1]=Temp;
}
}
void main()
{
char Message[ ]="PreboardExam";
Secret(Message);
cout<<Message<<endl;
}
2. Find the output of the following program:
# include <iostream.h>
# include <conio.h>
# include <stdlib.h>
void main ()
{
char serial[] = {'A', 'B', 'C', 'D'};
int number[] = { 2, 6, 7, 3};
clrscr();
randomize();
cout << " The winner is : ";
cout << serial [random(3)];
for (int i = 0; i < 4; i++)
cout << number[sizeof(int) + random(2) - 1 ];
getch();
}
Outputs:
(i)
(ii)
(iii)
(iv)
The winner is : A2776
The winner is : D6766
The winner is : B6767
The winner is : C3672
3. Define a class Taxpayer, whose class description is given below:Private Members:int pan - to store the personal account no.
char name[20] - to store the name
float taxableinc - to store the total annual taxable income.
float tax - to store the tax that is calculated.
computetax ( )- A function to compute tax from the following rule:Total Annual Taxable Income
Rate of Taxation
Up to 60000
0%
Greater than 60000, less than = 150000
5%
Above 150000, upto 500000
Above 500000
10%
15%
Public Members :inputdata ( ) - A function to enter the data and call the compute tax( ) function.
display( ) - To display the data.
4. Define a class Library in C++ with with the following specification
`Private Members:
B_code of type integers
Description of type string
No_of_pages of type integer
Price of type integer
A member function calculate( ) to calculate and return the price as
(No_of_pages* Price)
Public Members
(i)
A function Enter( ) to allow user to enter values for B_code,
Description, No_of_pages & call function calculate( ) to calculate the
price of the books.
(ii)
A function Disp( ) to allow user to view the content of all the data
members.
5. Define a class Travel in C++ with the following descriptions :
Private Members :
TravelCode of type long
Place of type character array (string)
No_of_travellers of type integer
No_of_buses of type integer
Public Members :
A function NewTravel() which allows user to enter TravelCode, Place and
No_of_travellers. Also, assign the value of No_of_buses as per the following
conditions :
No_of_travellers
No_of_buses
Less than 20
1
Equal to or more than 20 and less than 40
2
Equal to 40 or more than 40
3
A function ShowTravel( ) to display the content from all the data members on screen.
CHEMISTRY
1. SOLVE INTEXT QUESTIONS, SOLVED NUMERICAL PROBLEMS OF LESSION
I,II,II and IV
2. Write short notes on:
a) Denaturation of proteins
b) Invert sugar/inversion of sugar
c) Tranquilizers
d) Antibiotics
e) Analgesics
f) Antifertility Drugs
g) Artificial sweetning agents
h) Synthetic detergents
i) Antiseptics and disinfectants
Practice Paper
Class XII
CHEMISTRY
Q1State the magnetic behavior after heating of ZnO crystal.
(1)
Q2. 10 cm3 liquid A was mixed with 10 cm3 of liquid B. The volume of the resulting solution
was found to be 19.9 cm3. What do you conclude ?
(1)
Q3. Why is the vapour pressur of a solvent lowered when a non- volatile solute is dissolved in
it ? (1)
Q4. What is meant by limiting molar conductivity ?
(1)
Q5. From the given graph find the order of the reaction
6. define terms (i) Mole fraction
(ii)Van, t Hoff factor
(2)
7. In an ionic substance the anions Q form CCP lattice and P are distributed in the tetra and
octahedral voids . Determine the formula of the substance.
(2)
8. A chemical reaction is of second order with respect of a reactant . How will the rate of the
reaction be affected if the concentration of this reaction is ----(i) Doubled (2) Reduced to half
of initial. (2 )
9. Draw a plot molar conductivity Vs concentration. why Molar conductivity of both the
electrolytes strong well as well weak increases on decreasing concentration
(2)
10. (a) why the solids having metal excess defects are semiconductors?
(b) silver crystalizes in FCC lattice each side of the unit cell has a length of 490 pm. What
is the radius of an atom of the element.
(3)
11. what is activation energy ? The slop for the graph of log K Vs 1/T for the reaction
N2O5 ---
2NO2 +
1
2
O2
Is -5000. Calculate activation energy of the reaction.
(3)
12.state Henry,s . H2S is a toxic gas with rotten egg smell is used for the qualitative . If solubility
of theH2S in water is 0.195 m , calculate Henry, law constant.
13.The electrical resistance of a coloumn of 0.05 mol L-1 NaOH solution of diameter 1cm length
50 cm is5.55x10 3 ohm. Calculate its resistivity and molar conductivity.
(3)
14 State Raoult for the solution having non-volatile solute in it. Calculate the amount of sodium
chloride which must be added to one kilogram of water so that the its freezing point is depressed
by 3K. given Kf 1.86 K Kg mol- 1
( Na = 23, Cl = 35.5 )
(2+3)
15(a) What is meant by intrinsic semi conductor? Give one example.
(b) Sodium crystallizes in cubic lattice and the edge of the unit cell is 430 pm. Calculate the
number of atom in unit cell , density is 0.96 g/ cm-3.
(2+3)16.
16. (a) What is the role of ZnCl2 in dry cell ?
(b) Write the over all reaction in charging of the lead storage battery
(c) Write Nernst equation for the cell reaction:- Cu/ Cu2+ (0.130M) // Ag+ (1.0x10-4M) / Ag
Calculate the e.m. f. of this cell. E0Cu2+/Cu = 0.34V
,
E0Ag+/Ag = 0.8 v
(1+1+3)
17.What is pseudo uni molecular reaction ? Give an example.
The following results have been obtained during kinetic studies of the reaction
2A
+
B
----
C
+
D
Experiment
[A] /mol
L-1
[B] /mol L-1
Initial rate of formation of D/ mol
L-1
I
0.1
0.1
6.0 x10-3
II
0.3
0.2
7.2 x10-2
III
0.3
0.4
2.88 10 -1
Iv
0.4
0.1
2.4 x10-2
Determine the rate law and the rate constant for the reaction.
Geography
1. Do the self-study for the following topics –
Human development
International trade
Human settlement
2. Maintain a practical record for data – its source and compilation and data processing.
3. Has anyone migrated from your family? If so state the reasons and its consequences on
the financial background of your family.
4. From your point of view what can our government do to stop suicide of Indian farmers?
5. How is water crisis affecting the life of Indians? Elaborate by giving examples from
different states.
History
1. What are the main features of Mauryan Empire?
2. Describe the main features of early civilizations of India.
3. Name two sacrifices performed by the kings during the Vedic time.
4. Explain any two problems that were faced by Historians in writing history of Ancient
time.
5. State the factors that helped Magadha emerge as the most powerful Mahajanapada.
6. Describe the Varna system according to the Brahamanical texts.
7. Write the main teaching of Buddha .
8. “The Begums of Bhopal played a significant role in preserving the remains of Sanchi
stupa”
in 300 words
9. What kinds of duties were performed by Chandala according to Manu scripts?
10. Describe the marriages (various types) of Vedic period and Mahabharata period.
11. Describe the organization and the role of Buddhist Sanghas.
12. Describe the main features of Puranic Hinduism.
13. Self-study : Theme 14 & 15 (Understanding partition& framing the constitution)
Using the properties of determinants, show that
1.
1 x
yz
1 x
x2
1 y
zx
1 y
y2
1 z
xy
1 z
z2
1
2.
3.
4.
5.
7.
8.
9.
1
= (x – y)(y –z)(z – x)
=(    )(    )(   )
1 x y
x2  y2
1 yz
y2  z2
1 zx
z2  x2
= (x - y)(y - z)(z –x)
a a2
b.c
1 a2
a3
b b2
c.a
1 b2
b3
c2
a.b
1 c2
c3
c
1 a
a3
1 b
b3
1 c
c3
=
y
z
2
2
z2
y3
z3
x3
x
x2
yz
y
y
2
zx
z
2
xy
z
(C.B.S.E. 2006, 04)
(C.B.S.E. 2002, 1996C)
= (a - b) (b - c) (c - a) (ab + bc + ca)
= (a - b)(b - c)(c - a)(a + b + c)
x
y
(C.B.S.E. 1997, 92)
1
 

  
x
6.
=
= xyz(x – y)(y – z)(z – x)
(C.B.S.E. 1997)
(C.B.S.E. 1997, 96 ,2000, 2003C)
(C.B.S.E. 2000)
= (x – y)(y – z)(z – x) (xy + yz + zx)

2
 


2

2
    
yz
x
y
zx
z
x
x y
y
z
(C.B.S.E. 2007)
= (    )(    )(   ) (      ) )
= (x + y + z )(x – z)2
(C.B.S.E. 2008, 05)
(C.B.S.E. 2007)
10.
11.
x4
2x
2x
2x
x4
2x
2x
2x
x4
a
ab
a  2b
a  2b
a
ab
ab
a  2b
a.
2a
2a
2b
bca
2b
2c
2c
cab
a
b
c
b  c  2a
b
c
a
c  a  2b
1 a2  b2
2ab
1 a  b
2
2ab
 2a
2b
14.
a
16.
17.
= (a + b + c)
a  b  2c
13.
b
(C.B.S.E. 1996)
= 9 (a + b) b2
abc
12.
15.
= (5x + 4)(x – 4)2
(C.B.S.E. 2008, 02)
3
(C.B.S.E. 2007, 06, 04,2000C,1998,97)
= 2(a + b + c)
3
(C.B.S.E. 2006, 04, 1999)
 2b
2
2a
1 a2  b2

2
2
= 1 a  b

3
(C.B.S.E. 2008)
c
a b bc
ca
bc ca
a.  b
1 x
1
1
1
1 y
1
1
1
1 z
1 a
1
1
1
1 b
1
1
1
1 c
= a3 + b3 +c3 – 3abc
= x.y.z + x.y + y.z + z.x
 abc(1 
(C.B.S.E. 2006)
(C.B.S.E. 2008, 04, 03)
1 1 1
  )
a b c
(C.B.S.E. 2003C, 1998C)
18.
x y
yz
zx
x
y
z
yz
zx
x y
y
z
x
zx
x y
yz
z
x
y
=2
(C.B.S.E. 1999,2001,04, 04C,2007)
x 1 x  2 x  a
x2
19. If a, b, c are in A.P., prove that
x3 xb
x3 x4
xc
=0
(C.B.S.E. 2006, 05)
ax ax ax
ax ax ax
20. Using the properties, solve for x:
ax ax ax
=0
(C.B.S.E. 2005,04)
2. Solution of equations using matrix method
1. Using matrix method, solve the following system of equations :
(i)
2x – y + z = 3 ,
- x +2y – z = - 4 , x – 2y + 2z = 1
(ii) x + 2y – 3z = - 4 , 2x + 3y + 2z = 2 , 3x – 3y – 4z =11
(iii) 3x – 2y + 3z = 8 , 2x + y – z = 1 ,
4x – 3y + 2z = 4
(iv) x + y + z = 4 ,
2x – y + z = -1
(v) 2x + 3y + 3z = 5,
2x + y – 3z = -9 ,
x – 2y + z = - 4 ,
3x – y – 2z = 3
(C.B.S.E. 2008)
(C.B.S.E. 2008,07)
(C.B.S.E. 2008)
(C.B.S.E. 2008,05)
(C.B.S.E. 2007)
(vi) 2x + y – 3z = 13 , x + y – z = 6 ,
2x – y + 4z = -12
(C.B.S.E. 2006)
(vii) x + y + z = 1 ,
x – 2y + 3z = 2,
x – 3y + 5z = 3
(C.B.S.E. 2004)
(viii) 2x + 6y = 2 ,
3x – z = - 8 ,
2x – y + z = -3
(C.B.S.E. 2003)
2. Solve the following system of equations, using matrices :
2 3 10
4 6 5
6 9 20
 
 4,    1,  
2
x y z
x y z
x y z
(C.B.S.E. 2002 C)
1  2 0 
 2 1 3




0

2
1
3. Find A-1, where A = 
, Hence, solve the system of linear equations :
x – 2y = 10, 2x + y + 3z = 8, - 2y + z = 7.
(C.B.S.E. 1997)
 3 2 1 
2
1  3

 1 2
1 
If A = 
, find A-1, Using A-1 solve the following system of equations :
4.
+ z = 2, 2x + y – 3z – 5, - x + 2y +z = 6.
5.
Given that A =
4
 4 4
 7 1
3 

 5  3  1
(C.B.S.E. 1997)
1  1 1 
1  2  2


2 1
3 
and B =
, find AB and use it to
solve the system of equations : x –y + z = 4, x – 2y – 2z = 9, 2x + y + 3z = 1.
(C.B.S.E. 2003 C)
3x – 2y
Hindi