Group A Grammar
Q1Reported speech
He asked, "What is your name?" Choose the correct indirect speech.
- aHe asked what my name is.
- bHe asked what my name was.
- cHe asked what my was my name.
- dHe asked what were my name.
Answer (b): In reported speech the verb moves back a tense (is becomes was) and the question takes statement word order: what my name was.
Revise: Grammar and Usage (Class 11 notes)
Q2Conditionals
If I had met him, I .......... him easily.
- awould recognize
- bwould have recognize
- cwould have recognized
- drecognizes
Answer (c): A past unreal condition (if + past perfect) takes would have + past participle in the main clause.
Revise: Grammar and Usage (Class 11 notes)
Q3Causative verbs
My parents always make me ........ homework.
- ato do
- bdo
- cdone
- ddid
Answer (b): After make + object in the active voice we use the bare infinitive, so make me do.
Revise: Grammar and Usage (Class 11 notes)
Q4Spelling
The misspelled word is ........
- aseparate
- brecommendation
- caccommodation
- danxietie
Answer (d): The correct spelling is anxiety. The other three are spelled correctly.
Revise: Grammar and Usage (Class 11 notes)
Q5Question tags
Nobody was absent in the exam, .......?
- aweren't they
- bwere they
- cwas he
- dwasn't he
Answer (b): Nobody is negative in meaning, so the tag is positive. Nobody takes the plural pronoun they, giving were they.
Revise: Grammar and Usage (Class 11 notes)
Q6Conjunctions
She looks as if .......
- ashe is an actress
- bactress
- cfamous
- dacting
Answer (a): As if needs a full clause (subject + verb), so she is an actress.
Revise: Grammar and Usage (Class 11 notes)
Q7Parts of speech
The actress performed well. The word 'well' is a ........
- averb
- bnoun
- cadjective
- dadverb
Answer (d): Well tells how she performed, so it modifies a verb and is an adverb.
Revise: Grammar and Usage (Class 11 notes)
Q8Nouns
School education should enhance creativity. The word 'creativity' is a .......
- aconcrete noun
- babstract noun
- ccollective noun
- dcountable noun
Answer (b): Creativity is a quality or idea that cannot be touched, so it is an abstract noun.
Revise: Grammar and Usage (Class 11 notes)
Q9Word formation
In the word punishment, the 'ment' is ......
- aSuffix
- bPrefix
- cRoot word
- dNew word
Answer (a): An affix added at the end of a word is a suffix: punish + ment.
Revise: Vocabulary and Word Formation (Class 11 notes)
Q10Prepositions
He has been teaching ...... a long time.
- afor
- bsince
- cin
- dat
Answer (a): For is used with a length of time (a long time); since is used with a point in time.
Revise: Grammar and Usage (Class 11 notes)
Q11Tenses
Prem is on holiday. He ...... to Ilam.
- ahas go
- bhas gone
- cwent
- dhas been going
Answer (b): The present result (he is away now) needs the present perfect: has gone.
Revise: Grammar and Usage (Class 11 notes)
Q13Articles
I have ........ headache.
- aan
- ba
- cthe
- dnone of above
Answer (b): Headache begins with a consonant sound, and it is a singular countable noun here, so a.
Revise: Grammar and Usage (Class 11 notes)
Q14Wish clauses
I wish I ...... BCA entrance exam.
- apass
- bcan pass
- cwould pass
- dwill pass
Answer (c): Wish about a future wanted outcome takes would + verb. Pass, can pass and will pass do not follow the wish pattern.
Revise: Grammar and Usage (Class 11 notes)
Q15Voice
What is the passive voice of 'Nadine Gordimer wrote The Conservationist'?
- aThe Conservationist was written by Nadine Gordimer.
- bThe Conservationist has been written by Nadine Gordimer.
- cThe Conservationist written by Nadine Gordimer.
- dThe Conservationist was wrote by Nadine Gordimer.
Answer (a): Simple past active becomes was/were + past participle: was written by.
Revise: Grammar and Usage (Class 11 notes)
Q16Connectors
........... the hard labor, she was successful.
- abecause
- bbecause of
- calthough
- ddespite
Answer (d): A noun phrase (the hard labor) follows despite, which shows contrast. Although needs a clause.
Revise: Grammar and Usage (Class 11 notes)
Q17Tenses
As soon as he opened the fridge, he ......... some oranges.
- ahad seen
- bsaw
- chas seen
- dsees
Answer (b): Both actions are in the past and follow quickly, so simple past: saw.
Revise: Grammar and Usage (Class 11 notes)
Q18Subject-verb agreement
The driver and mechanic ....... intelligent enough to handle the problem.
- aare
- bis
- chave
- dhas
Answer (a): Two subjects joined by and take a plural verb: are.
Revise: Grammar and Usage (Class 11 notes)
Q19Either, neither
He is weak, and he is still in bed. He has not stopped medicines .......
- aeither
- bneither
- ceither or
- dneither nor
Answer (a): With a negative verb, either at the end of the sentence adds a second negative idea.
Revise: Grammar and Usage (Class 11 notes)
Q20Adverbs
It was raining very .........
- aheavy
- bheavily
- cwith heavy
- dwith heavily
Answer (b): An adverb is needed to modify the verb raining, and heavily fits.
Revise: Grammar and Usage (Class 11 notes)
Q21Word order
Which one is correct?
- aI visit him in the supermarket sometimes.
- bI visit him sometimes in the supermarket.
- cI visit sometimes him in the supermarket.
- dI sometimes visit him in the supermarket.
Answer (d): Frequency adverbs such as sometimes usually come before the main verb.
Revise: Grammar and Usage (Class 11 notes)
Q22Subject-verb agreement
Travelling to the remote places ....... important because it is adventurous.
- ais
- bare
- cwas
- dwere
Answer (a): Travelling is a gerund subject, singular, and the statement is a general truth, so is.
Revise: Grammar and Usage (Class 11 notes)
Q23Vocabulary
The word resemblance means ........
- alasting only for a short time
- bthe state of being alike
- cvictory over a place or people by use of military force
- dliquid that is believed to cure all ills
Answer (b): Resemblance is similarity between things, or being alike.
Revise: Vocabulary and Word Formation (Class 11 notes)
Q24Tenses
I went to see the film, but I .............. it.
- ado not enjoy
- bdid not enjoy
- chas not enjoyed
- denjoyed
Answer (b): The sentence is in the past and but shows contrast, so did not enjoy.
Revise: Grammar and Usage (Class 11 notes)
Q25Participial adjectives
Are you ........ in technical subject?
- ainteresting
- binterested
- cinterest
- dall of them
Answer (b): Be interested in is the fixed phrase for a person's feeling.
Revise: Grammar and Usage (Class 11 notes)
Q26Language functions
I'll tell your parents what you did. The language function in this sentence is .......
- aDeciding
- bThreatening
- cPredicting a future action
- dPromising
Answer (b): Telling parents about someone's wrongdoing as a warning is a threat.
Revise: Grammar and Usage (Class 11 notes)
Q27Subject-verb agreement
Everyone ...... problems in their life.
- ahas
- bhave
- chad
- dhas had
Answer (a): Everyone is singular and the statement is a general truth in the present: has.
Revise: Grammar and Usage (Class 11 notes)
Q28Vocabulary
Collin studied Science reluctantly due to her father's pressure. It means
- aCollin was eager to read Science.
- bCollin was not eager to read Science.
- cCollin was eager to read Science for father
- dCollin was eager to read not Science but Math.
Answer (b): Reluctantly means unwillingly, so she was not eager.
Revise: Vocabulary and Word Formation (Class 11 notes)
Q29Connectors
.......the fact that he is an octogenarian; he still leads an active life.
- ahowever
- balthough
- cin spite of
- dbecause
Answer (c): A noun phrase (the fact that ...) follows in spite of. Although and however do not fit this structure.
Revise: Grammar and Usage (Class 11 notes)
Q30Modals
You look tired. You ....... to the bed.
- acan go
- bshould go
- cwill go
- dmay
Answer (b): Giving advice uses should.
Revise: Grammar and Usage (Class 11 notes)
Q31Possessives
The monkey has ..... leg hurt.
- aits
- bit's
- cits'
- dit
Answer (a): Its is the possessive form. It's means it is.
Revise: Grammar and Usage (Class 11 notes)
Q32Relative clauses
That's the house ...... I was born.
- athere
- bwhere
- cthat
- dwhich
Answer (b): Where is the relative adverb for a place.
Revise: Grammar and Usage (Class 11 notes)
Q33Verb forms, homophones
Krishna could not ...... the branch off the tree.
- abreak
- bbrake
- cbroke
- dbreek
Answer (a): After could not use the base verb: break. Brake is a different word.
Revise: Grammar and Usage (Class 11 notes)
Q34Literature
'The Selfish Giant' is a short story for children written by
- aOscar Wilde
- bLeo Tolstoy
- cChinua Achebe
- dR.K. Narayan
Answer (a): The Selfish Giant is a fairy tale by Oscar Wilde.
Revise: The Selfish Giant (Class 11 notes)
Q35Phrasal verbs
Why are you bringing that argument ...... now?
- aup
- binto
- cto
- dabout
Answer (a): Bring up means to raise a topic for discussion.
Revise: Grammar and Usage (Class 11 notes)
Q36Reading comprehension
Read the passage (teaching as the most privatized public profession). What is the problem of teaching according to Palmer?
- aTeaching as public profession
- bTeaching as private profession
- cTeaching as dream
- dTeaching as anxiety
Answer (b): Palmer calls teaching the most privatized of the public professions, because teachers work alone behind closed doors.
Revise: Reading Comprehension (Class 11 notes)
Q37Reading comprehension
Read the passage (teaching as the most privatized public profession). According to the passage, teachers prefer to .......
- ateach in isolation
- bteach in collaboration with other teachers
- cteach sharing experiences
- dteach in semester class
Answer (a): The passage says teachers almost always teach solo and close the door on colleagues.
Revise: Reading Comprehension (Class 11 notes)
Q38Reading comprehension
Read the passage (teaching as the most privatized public profession). The privatization is now breaking down in the United State because of .......
- aInternet
- bonline classes
- chigher education
- dnew syllabus
Answer (a): The passage names widespread use of the internet to circulate syllabi and publish course evaluations.
Revise: Reading Comprehension (Class 11 notes)
Q39Vocabulary
Read the passage (teaching as the most privatized public profession). The word 'rarely' means
- aalways
- bsometimes
- cseldom
- dnever
Answer (c): Rarely means not often, which is seldom.
Revise: Vocabulary and Word Formation (Class 11 notes)
Q40Reading comprehension
Read the passage (teaching as the most privatized public profession). 'We' in the fourth line of the passage refers to ......
- aLawyers
- bSurgeons
- cTeachers
- dAll of them
Answer (c): Palmer says 'we teach in front of students', so we means teachers.
Revise: Reading Comprehension (Class 11 notes)
Group B Mathematics
Q41Sets
If $n(A)=30$, $n(B)=50$, $n(U)=60$ and $n(A\cup B)=55$, then the sum of $n(A-B)$ and $n(B-A)$ is equal to
- a45
- b50
- c55
- d30
Answer (d): $n(A\cap B)=30+50-55=25$. So $n(A-B)=5$, $n(B-A)=25$ and the sum is $30$.
Revise: Algebra (Class 11 notes)
Q42Series
The sum of natural numbers from 1 to 20 is
- a$\frac{20\times21}{2}$
- b$\frac{19\times21}{2}$
- c$\frac{1\times20}{2}$
- d200
Answer (a): Sum of first $n$ natural numbers is $\frac{n(n+1)}{2}$, so $\frac{20\times21}{2}=210$.
Revise: Algebra (Class 11 notes)
Q43Sets
If $n(A)=26$ and $n(B)=32$ then the maximum value of $n(A\cap B)$ is
- a26
- b58
- c32
- d6
Answer (a): The intersection cannot be larger than the smaller set, so the maximum is 26.
Revise: Algebra (Class 11 notes)
Q44Number theory
For some integer n, which of the following forms is always an odd integer? - an
- b$n+1$
- c2n
- d$2n+1$
Answer (d): $2n$ is always even, so $2n+1$ is always odd.
Revise: Algebra (Class 11 notes)
Q45Functions
The range of the function $f(x)=\sqrt{x-1}$ is
- a$[1,\infty)$
- b$(-\infty,+\infty)$
- c$(-1,\infty)$
- d$[0,\infty)$
Answer (d): A square root gives non-negative values, and it takes every value from 0 upward, so the range is $[0,\infty)$. ($[1,\infty)$ is the domain.)
Revise: Algebra (Class 11 notes)
Q46Geometric series
For the infinite sum of a geometric series to exist, its ratio should be
- aless than 0
- bless than −1
- cbetween $1$ and $-1$
- dgreater than 1
Answer (c): The infinite sum converges only when $|r|<1$, that is, $-1<r<1$.
Revise: Algebra (Class 11 notes)
Q47Complementary angles
The complement of an angle is $20^\circ$ less than 4 times the angle. Then the angle is
- a38
- b90
- c22
- d70
Answer (c): $90-x=4x-20$, so $5x=110$ and $x=22$.
Revise: Trigonometry (Class 11 notes)
Q48Quadratic equations
If the quadratic equation is $x^2+x+1=0$ then $x=$
- a$\frac{-1\pm i\sqrt3}{2}$
- b$\frac{-1-i\sqrt3}{2}$
- c$\frac{-1\pm i\sqrt2}{2}$
- d$\frac{-1+i\sqrt3}{2}$
Answer (a): $x=\frac{-1\pm\sqrt{1-4}}{2}=\frac{-1\pm i\sqrt3}{2}$. Both signs are roots, so option a is complete.
Revise: Algebra (Class 11 notes)
Q49Inverse functions
A function is defined as $f(x)=\frac{3x+1}{4}$. Its inverse is
- a$\frac{4x-1}{3}$
- b$\frac{4x+1}{3}$
- c$\frac{3x-1}{4}$
- d$\frac{3x+1}{4}$
Answer (a): Put $y=\frac{3x+1}{4}$, so $x=\frac{4y-1}{3}$. Swap to get $f^{-1}(x)=\frac{4x-1}{3}$.
Revise: Algebra (Class 11 notes)
Q50Polynomials
One factor of the polynomial $x^3-4x^2+x+6$ is $(x-2)$. The two other factors are
- a$(x+1)(x-3)$
- b$(x+2)(x-2)$
- c$(x+3)(x-1)$
- d$(x+4)(x+1)$
Answer (a): Dividing by $(x-2)$ gives $x^2-2x-3=(x-3)(x+1)$.
Revise: Algebra (Class 11 notes)
Q51Infinite series
The sum of the infinite series $1+\frac12+\frac14+\frac18+\cdots$ is
- a4
- b3
- c2
- d1
Answer (c): Here $a=1$, $r=\frac12$, so $S=\frac{a}{1-r}=\frac{1}{1/2}=2$.
Revise: Algebra (Class 11 notes)
Q52Series
The sum of cubes of the first 6 natural numbers is
- a661
- b551
- c441
- d331
Answer (c): $\left(\frac{6\cdot7}{2}\right)^2=21^2=441$.
Revise: Algebra (Class 11 notes)
Q53Heights and distances
A pole at a distance of 25 m from the observer makes an angle of $60^\circ$ at its top. Then the height of the pole is
- a25
- b$25\sqrt3$
- c$\frac{25}{2}$
- d$50\sqrt3$
Answer (b): $h=25\tan60^\circ=25\sqrt3$.
Revise: Trigonometry (Class 11 notes)
Q54Discount
Marked price of an article is Rs. 8500. If a discount of 10% is allowed, the selling price is
- a7550
- b7650
- c7750
- d7850
Answer (b): Discount $=850$, so selling price $=8500-850=7650$.
Revise: Algebra (Class 11 notes)
Q55Currency exchange
If 7 pounds = 11 US dollars and 2 US dollars = Rs. 213, how many pounds can be exchanged for Rs. 117150?
- a750
- b650
- c700
- d850
Answer (c): Rs. 117150 equals $\frac{117150\times2}{213}=1100$ US dollars. Then the pounds are $\frac{1100\times7}{11}=700$.
Revise: Algebra (Class 11 notes)
Q56Profit and loss
A mobile is sold for Rs. 11000 with a profit of Rs. 1000. The percentage profit is
- a9%
- b10%
- c12%
- d14%
Answer (b): Cost price $=11000-1000=10000$. Profit % $=\frac{1000}{10000}\times100=10%$.
Revise: Algebra (Class 11 notes)
Q57Time and work
If 12 girls or 8 boys can do a piece of work in 3 days, how many days are required for 4 boys and 6 girls to do the same work?
- a2
- b4
- c5
- d3
Answer (d): 12 girls equal 8 boys, so 6 girls equal 4 boys. Then 4 boys and 6 girls equal 8 boys, who need 3 days.
Revise: Algebra (Class 11 notes)
Q58Pair of lines
A single equation represented by the two straight lines $x=2y$ and $2x=y$ is
- a$2x^2-3xy+y^2=0$
- b$x^2-3xy+2y^2=0$
- c$2x^2-xy+2y^2=0$
- d$2x^2-5xy+2y^2=0$
Answer (d): $(x-2y)(2x-y)=2x^2-xy-4xy+2y^2=2x^2-5xy+2y^2=0$.
Revise: Analytic geometry (Class 11 notes)
Q59Circle theorems
Two angles subtended by an arc, one at the center and the other at the circumference, are related as
- aThe angle at the center is double the angle at the circumference.
- bThe angle at the circumference is double the angle at the center.
- cThe angle at the center is half the angle at the circumference.
- dThe angle at the circumference is equal to the angle at the center.
Answer (a): Circle theorem: the angle at the centre is twice the angle at the circumference on the same arc.
Revise: Analytic geometry (Class 11 notes)
Q60Composite functions
If $f(x)=4x$, $g(x)=x+1$ and $fog(x)=20$ then $x=$
- a1
- b3
- c2
- d4
Answer (d): $f(g(x))=4(x+1)=20$, so $x+1=5$ and $x=4$.
Revise: Algebra (Class 11 notes)
Q61Probability
If two children are born in a family, find the probability that both are girls.
- a$\frac12$
- b$\frac13$
- c$\frac14$
- d$\frac23$
Answer (c): Outcomes: GG, GB, BG, BB. Only one is GG, so $\frac14$.
Revise: Statistics and Probability (Class 11 notes)
Q62Trigonometric ratios
The value of $\tan75^\circ$ is
- a$\sqrt3$
- b$2+\sqrt3$
- c$2-\sqrt3$
- d2
Answer (b): $\tan(45+30)=\frac{1+1/\sqrt3}{1-1/\sqrt3}=\frac{\sqrt3+1}{\sqrt3-1}=2+\sqrt3$.
Revise: Trigonometry (Class 11 notes)
Q63Arithmetic progression
The sum of 15 terms of an A.P. is 435 and the common difference is 4. The first term is
- a4
- b3
- c2
- d1
Answer (d): $\frac{15}{2}(2a+14\cdot4)=435$ gives $2a+56=58$, so $a=1$.
Revise: Algebra (Class 11 notes)
Q64Logarithms
Which one is the same as $\log 8$?
- a$\log4+\log2$
- b$\log4+\log4$
- c$2\log4$
- d$4\log2$
Answer (a): $\log4+\log2=\log(4\times2)=\log8$.
Revise: Algebra (Class 11 notes)
Q65Matrices
If $A=\begin{pmatrix}2&3\-4&-5\end{pmatrix}$ and $B=\begin{pmatrix}0&-3\2&5\end{pmatrix}$ then $(AB)^T=$
- a$\begin{pmatrix}6&-10\9&-13\end{pmatrix}$
- b$\begin{pmatrix}6&10\9&-13\end{pmatrix}$
- c$\begin{pmatrix}6&-10\9&13\end{pmatrix}$
- d$\begin{pmatrix}6&0\9&3\end{pmatrix}$
Answer (a): $AB=\begin{pmatrix}6&9\-10&-13\end{pmatrix}$. Its transpose swaps rows and columns.
Revise: Algebra (Class 11 notes)
Q66Vectors
If $\vec a=(0,3,4)$ and $\vec b=(2,-2,0)$, the cosine of the angle between them is
- a$-\frac{3}{\sqrt2}$
- b$\frac{3}{\sqrt2}$
- c$-\frac{3}{5\sqrt2}$
- d$\frac{3}{5\sqrt2}$
Answer (c): $\vec a\cdot\vec b=0-6+0=-6$, $|\vec a|=5$, $|\vec b|=2\sqrt2$, so $\cos\theta=\frac{-6}{10\sqrt2}=-\frac{3}{5\sqrt2}$. The paper prints options c and d identically as $\frac{3}{5\sqrt2}$, a lost minus sign in one of them, so option c is restored as $-\frac{3}{5\sqrt2}$.
Revise: Vectors (Class 11 notes)
Q67Means
The harmonic mean between two numbers $a$ and $b$ is
- a$\frac{a+b}{2ab}$
- b$\frac{a-b}{2ab}$
- c$\frac{2ab}{a+b}$
- d$\frac{2ab}{a-b}$
Answer (c): Harmonic mean is the reciprocal of the mean of the reciprocals: $\frac{2ab}{a+b}$.
Revise: Algebra (Class 11 notes)
Q68Series
The sum of the first 10 odd numbers is
- a80
- b90
- c125
- d100
Answer (d): The sum of the first $n$ odd numbers is $n^2=100$.
Revise: Algebra (Class 11 notes)
Q69Complex numbers
The solution of the equation $x^2+1=0$ in the complex number system is
- a1
- b−1
- c0
- d±i
Answer (d): $x^2=-1$, so $x=\pm i$.
Revise: Algebra (Class 11 notes)
Q70Sequences
The next term of the sequence $1,2,4,7,11,\ldots$ is
- a15
- b16
- c17
- d22
Answer (b): The differences are 1, 2, 3, 4, so the next difference is 5 and the term is $11+5=16$.
Revise: Algebra (Class 11 notes)
Q71Functions
If $f(x)=x^2-3x+1$ and $f(2a)=2f(a)$ then $a=$
- a$\frac1{\sqrt2}$
- b$-\frac1{\sqrt2}$
- c$\frac1{\sqrt2}$ or $-\frac1{\sqrt2}$
- d1
Answer (c): $4a^2-6a+1=2a^2-6a+2$ gives $2a^2=1$, so $a=\pm\frac1{\sqrt2}$.
Revise: Algebra (Class 11 notes)
Q72Absolute value
If $x<0$, then $|x|$ is equal to
- ax
- b−x
- c$x^2$
- d$-x^2$
Answer (b): For negative $x$, the absolute value is $-x$, which is positive.
Revise: Algebra (Class 11 notes)
Q73Linear equations
The two lines $3x+2y=5$ and $9x+6y=14$ have
- ano solution
- bunique solution
- cinfinite solution
- dtwo solution
Answer (a): The coefficients are in ratio $3:1$ but the constants are not ($5\cdot3\ne14$), so the lines are parallel and distinct: no solution.
Revise: Analytic geometry (Class 11 notes)
Q74Transformations
A point $(3,4)$ is rotated $90^\circ$ anticlockwise and then translated by $(5,-2)$. The resulting point is
- a$(1,1)$
- b$(8,2)$
- c$(-2,6)$
- d$(0,1)$
Answer (a): Rotation by $90^\circ$ gives $(x,y)\to(-y,x)=(-4,3)$. Adding $(5,-2)$ gives $(1,1)$.
Revise: Analytic geometry (Class 11 notes)
Q75Remainder theorem
If $2x^3-7x^2+x+10=(x-1)Q(x)+R(x)$ then the remainder $R(x)$ is
- a5
- b6
- c7
- d9
Answer (b): By the remainder theorem $R=f(1)=2-7+1+10=6$.
Revise: Algebra (Class 11 notes)
Q76Exponents
If $5^{x+3}=(25)^x$ then $x=$
- a1
- b2
- c0
- d3
Answer (d): $5^{x+3}=5^{2x}$, so $x+3=2x$ and $x=3$.
Revise: Algebra (Class 11 notes)
Q77Algebraic identities
If $x+y=3$ and $x^2+y^2=5$ then $xy=$
- a1
- b2
- c3
- d453
Answer (b): $(x+y)^2=x^2+y^2+2xy$ gives $9=5+2xy$, so $xy=2$.
Revise: Algebra (Class 11 notes)
Q78Pair of lines
If $m_1$ and $m_2$ are the slopes of the pair of lines $ax^2+2hxy+by^2=0$ then $m_1m_2$ is
- a$\frac{2h}{b}$
- bab
- c$a-b$
- d$\frac ab$
Answer (d): Putting $y=mx$ gives $bm^2+2hm+a=0$, so the product of roots is $\frac ab$.
Revise: Analytic geometry (Class 11 notes)
Q79Circle
In the general equation of a circle $x^2+y^2+2gx+2fy+c=0$ the centre of the circle is
- a$(g,f)$
- b$(f,g)$
- c$(-g,-f)$
- d$(-f,-g)$
Answer (c): Completing the squares gives $(x+g)^2+(y+f)^2=g^2+f^2-c$, so the centre is $(-g,-f)$. The paper prints 'radius', a misprint for 'centre', since every option is a coordinate pair.
Revise: Analytic geometry (Class 11 notes)
Q80Factorial
- a0
- b−1
- c1
- d2
Answer (c): By definition $0!=1$.
Revise: Algebra (Class 11 notes)
Q82Derivatives
The derivative of $\tan x$ with respect to $x$ is
- a$\sin^2x$
- b$\cos^2x$
- c$\csc^2x$
- d$\sec^2x$
Answer (d): Standard result: $\frac{d}{dx}\tan x=\sec^2x$.
Revise: Calculus (Class 11 notes)
Q833D coordinates
A point in three-dimensional space has coordinates $(1,2,-2)$. Its distance from the origin is
- a5
- b4
- c1
- d3
Answer (d): $\sqrt{1+4+4}=3$.
Revise: Vectors (Class 11 notes)
Q84Matrices
A matrix $A$ has order $3\times4$ and $B$ has order $4\times3$. The order of $AB$ is
- a$3\times3$
- b$4\times4$
- c$4\times3$
- d$3\times4$
Answer (a): $(3\times4)(4\times3)$ gives rows of $A$ by columns of $B$: $3\times3$.
Revise: Algebra (Class 11 notes)
Q85Matrices
If the transpose of a matrix $A$ is $A$ itself, then $A$ is called
- aidentity
- bscalar
- csymmetric
- dskew-symmetric
Answer (c): $A^T=A$ is the definition of a symmetric matrix.
Revise: Algebra (Class 11 notes)
Q86Series
The sum $1^3+2^3+3^3+\cdots+n^3$ is
- a$\left(\frac{n(n+1)}{2}\right)^3$
- b$\left(\frac{n(n+1)}{2}\right)^2$
- c$\left(\frac{n(n+1)}{3}\right)^2$
- d$\left(\frac{n(n-1)}{2}\right)^2$
Answer (b): The sum of cubes equals the square of the sum of the first n numbers.
Revise: Algebra (Class 11 notes)
Q87Sequences
The fifth term of the sequence $\frac12,\frac45,\frac78,\ldots$ is
- a$\frac{11}{12}$
- b$\frac{12}{13}$
- c$\frac{13}{14}$
- d$\frac{14}{15}$
Answer (c): Numerators go 1, 4, 7 (add 3) and denominators 2, 5, 8 (add 3). The fifth term is $\frac{13}{14}$.
Revise: Algebra (Class 11 notes)
Q88Mensuration
The radius of a cylinder is 7 cm and its height is 3 cm. Its volume is
- a$442\ cm^3$
- b$452\ cm^3$
- c$462\ cm^3$
- d$472\ cm^3$
Answer (c): $V=\pi r^2h=\frac{22}{7}\times49\times3=462$.
Revise: Algebra (Class 11 notes)
Q89Nature of roots
If $b^2-4ac=0$ then the roots of $ax^2+bx+c=0$ are
- areal and equal
- breal and unequal
- cirrational
- dimaginary
Answer (a): A zero discriminant means two equal real roots.
Revise: Algebra (Class 11 notes)
Q90Probability
A die is thrown. The probability of getting an odd number is
- a$\frac13$
- b$\frac12$
- c$\frac34$
- d2
Answer (b): Odd faces are 1, 3, 5, so $\frac36=\frac12$.
Revise: Statistics and Probability (Class 11 notes)