Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

This section includes 8666 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.

351.

Let A and B be two events such that \[P(A\cap B')=0.20,P(A'\cap B)=0.15,\]\[P(A'\cap B')=0.1,\] Then \[P(A/B)\] is equal to

A. 41944
B. 44502
C. 44379
D. 44378
Answer» B. 44502
352.

If (2, 3, 5) is one end of a diameter of the sphere \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}-6x-12y-2z+20=0\]then co-ordinates of the other end of the diameter are              [Kerala (Engg.) 2005]

A. (4, 3, 5)
B. (4, 9, -3)
C. (4, 9, 3)
D. (4, 3, -3)
E. (4, 9, 5)
Answer» C. (4, 9, 3)
353.

If a, b, c are any vectors, then the true statement is                                          [RPET 1988]

A. \[\mathbf{a}\times (\mathbf{b}\times \mathbf{c})=(\mathbf{a}\times \mathbf{b})\times \mathbf{c}\]
B. \[\mathbf{a}\times \mathbf{b}=\mathbf{b}\times \mathbf{a}\]
C. \[\mathbf{a}\,.\,(\mathbf{b}\times \mathbf{c})=\mathbf{a}\,.\,\mathbf{b}\times \mathbf{a}\,.\,\mathbf{c}\]
D. \[\mathbf{a}\,.\,(\mathbf{b}-\mathbf{c})=\mathbf{a}\,.\,\mathbf{b}-\mathbf{a}\,.\,\mathbf{c}\]
Answer» E.
354.

If the circles \[{{x}^{2}}+{{y}^{2}}={{a}^{2}}\]and \[{{x}^{2}}+{{y}^{2}}-2gx+{{g}^{2}}-{{b}^{2}}=0\] touch each other externally, then

A. \[g=ab\]
B. \[{{g}^{2}}={{a}^{2}}+{{b}^{2}}\]
C. \[{{g}^{2}}=ab\]
D. \[g=a+b\]
Answer» E.
355.

Let \[\mathbf{a},\,\mathbf{b},\,\mathbf{c}\] be three vectors such that \[\mathbf{a}\ne 0,\] and \[\mathbf{a}\times \mathbf{b}=2\mathbf{a}\times \mathbf{c},\,\,|\mathbf{a}|\,=\,|\mathbf{c}|\,=\,1,\,|\mathbf{b}|\,=4\] and \[|\mathbf{b}\times \mathbf{c}|\,=15.\] If \[\mathbf{b}-2\mathbf{c}=\lambda \mathbf{a},\] then l equals to [Orissa JEE 2004]

A. 1
B. \[\pm \,4\]
C. 3
D. ? 2
Answer» C. 3
356.

Consider the sequence \[8A+2B,\text{ }6A+B,\text{ }4A,\,\,2A-B,........\]  Which term of this sequence will have a coefficient of A which is twice the coefficient of B?

A. 10th
B. 14th
C. 16th
D. None of these
Answer» E.
357.

If \[P=n({{n}^{2}}-{{1}^{2}})({{n}^{2}}-{{2}^{2}})({{n}^{2}}-{{3}^{2}})...({{n}^{2}}-{{r}^{2}}),\] \[n>r,n\in N\] then P is necessarily divisible by

A. \[(2r+2)!\]
B. \[(2r+4)!\]
C. \[(2r+1)!\]
D. None of these
Answer» D. None of these
358.

A sample of 4 items is drawn at a random without replacement from a lot of 10 items. Containing 3 defective. If X denotes the number of defective items in the sample then \[P(0

A. \[\frac{3}{10}\]
B. \[\frac{4}{5}\]
C. \[\frac{1}{2}\]
D. \[\frac{1}{6}\]
Answer» C. \[\frac{1}{2}\]
359.

\[\frac{\sin 3\theta +\sin 5\theta +\sin 7\theta +\sin 9\theta }{\cos 3\theta +\cos 5\theta +\cos 7\theta +\cos 9\theta }=\] [Roorkee 1973]

A. \[\tan 3\theta \]
B. \[\cot 3\theta \]
C. \[\tan 6\theta \]
D. \[\cot 6\theta \]
Answer» D. \[\cot 6\theta \]
360.

If \[A=\left[ \begin{matrix}    \lambda  & 1  \\    -1 & -\lambda   \\ \end{matrix} \right]\], then for what value of \[\lambda ,\,{{A}^{2}}=O\]  [MP PET 1992]

A. 0
B. \[\pm \text{ }1\]
C. -1
D. 1
Answer» C. -1
361.

A student appears for tests I, II and III. The student is successful if he passes either in tests I and II or tests I and IV. The probabilities of the student passing in tests I, II, III are p, q and \[\frac{1}{2}\] respectively. The probability that the student is successful is \[\frac{1}{2}\] then the relation between p and q is given by

A. \[pq+p=1\]
B. \[{{p}^{2}}+q=1\]
C. \[pq-1=p\]
D. None of these
Answer» B. \[{{p}^{2}}+q=1\]
362.

A die is rolled three times. Let \[{{E}_{1}}\] denote the event of getting a number larger than the previous number each time and \[{{E}_{2}}\] denote the event that the numbers (in order) form an increasing AP then

A. \[P({{E}_{2}})\ge P({{E}_{1}})\]
B. \[P({{E}_{2}}\cap {{E}_{1}})=\frac{3}{10}\]
C. \[P({{E}_{2}}/{{E}_{1}})=\frac{1}{36}\]
D. \[P({{E}_{1}})=\frac{10}{3}P({{E}_{2}})\]
Answer» E.
363.

A pair of fair dice is thrown independently three times. The probability of getting a score of exactly 9 twice is

A. 8/729
B. 8/243
C. 1/729
D. 8/9
Answer» C. 1/729
364.

The equation to the locus of a point which moves so that its distance from x-axis is always one half its distance from the origin, is

A. \[{{x}^{2}}+3{{y}^{2}}=0\]
B. \[{{x}^{2}}-3{{y}^{2}}=0\]
C. \[3{{x}^{2}}+{{y}^{2}}=0\]
D. \[3{{x}^{2}}-{{y}^{2}}=0\]
Answer» C. \[3{{x}^{2}}+{{y}^{2}}=0\]
365.

All the words that can be formed using alphabets A, H, L, U and R are written as in a dictionary (no alphabet is repeated). Rank of the word RAHUL is

A. 71
B. 72
C. 73
D. 74
Answer» E.
366.

The   vectors   \[\overrightarrow{AB}=3\hat{i}+5\hat{j}+4\hat{k}\]   and \[\overrightarrow{AC}=5\hat{i}-5\hat{j}+2\hat{k}\] are the sides of a triangle ABC. The length of the median through A is:

A. \[\sqrt{13}\]units
B. \[2\sqrt{5}\] units
C. 5 units
D. 10 units
Answer» D. 10 units
367.

If \[\vec{a},\text{ }\vec{b}\] and \[\vec{c}\] are the position vectors of the vertices of an equilateral triangle whose orthocentre is at the origin, then which one of the following is correct?

A. \[\vec{a}+\vec{b}+\vec{c}=\vec{0}\]
B. \[\vec{a}+\vec{b}+\vec{c}=\,\,unit\,\,vector\]
C. \[\vec{a}+\vec{b}=\vec{c}\]
D. \[\vec{a}=\vec{b}+\vec{c}\]
Answer» B. \[\vec{a}+\vec{b}+\vec{c}=\,\,unit\,\,vector\]
368.

A force \[F=2i+j-k\] acts at a point A, whose position vector is \[2i-j\]. The moment of F about the origin is

A. \[i+2j-4k\]
B. \[i-2j-4k\]
C. \[i+2j+4k\]
D. \[i-2j+4k\]
Answer» D. \[i-2j+4k\]
369.

The angle between the two tangents from the origin to the circle \[{{(x-7)}^{2}}+{{(y+1)}^{2}}=25\] is [MNR 1990; RPET 1997; DCE 2000]

A. 0
B. \[\frac{\pi }{3}\]
C. \[\frac{\pi }{6}\]
D. \[\frac{\pi }{2}\]
Answer» E.
370.

The solution of differential equation \[dy-\sin x\sin ydx=0\] is [MP PET 1996]

A. \[{{e}^{\cos x}}\tan \frac{y}{2}=c\]
B. \[{{e}^{\cos x}}\tan y=c\]
C. \[\cos x\tan y=c\]
D. \[\cos x\sin y=c\]
Answer» B. \[{{e}^{\cos x}}\tan y=c\]
371.

The number of solutions for the equation \[{{x}^{2}}-5|x|+\,6=0\] is [Karnataka CET 2004]

A. 4
B. 3
C. 2
D. 1
Answer» B. 3
372.

If \[1+\cot \theta =\text{cosec}\theta \], then the general value of \[\theta \] is  [Roorkee 1981]

A. \[n\pi +\frac{\pi }{2}\]
B. \[2n\pi -\frac{\pi }{2}\]
C. \[2n\pi +\frac{\pi }{2}\]
D. None of these
Answer» D. None of these
373.

The area between the curve \[y=4+3x-{{x}^{2}}\] and  x-axis is                                                                       [RPET 2001]

A. 125/6
B. 125/3
C. 125/2
D. None of these
Answer» B. 125/3
374.

The locus of the centres of the circles which touch externally the circles \[{{x}^{2}}+{{y}^{2}}={{a}^{2}}\]and \[{{x}^{2}}+{{y}^{2}}=4ax\], will be

A. \[12{{x}^{2}}-4{{y}^{2}}-24ax+9{{a}^{2}}=0\]
B. \[12{{x}^{2}}+4{{y}^{2}}-24ax+9{{a}^{2}}=0\]
C. \[12{{x}^{2}}-4{{y}^{2}}+24ax+9{{a}^{2}}=0\]
D. \[12{{x}^{2}}+4{{y}^{2}}+24ax+9{{a}^{2}}=0\]
Answer» B. \[12{{x}^{2}}+4{{y}^{2}}-24ax+9{{a}^{2}}=0\]
375.

Three expressions are given below:\[{{Q}_{1}}=\sin (A+B)+\sin (B+C)+\sin (C+A)\]\[{{Q}_{2}}=\cos (A-B)+\cos (B-C)+\cos (C-A)\]\[{{Q}_{3}}=\sin A(\cos B+\cos C)+\sin B(\cos C+\cos A)+\]\[\sin C(\cos A+\cos B)\]Which one of the following is correct?

A. \[{{Q}_{1}}={{Q}_{2}}\]
B. \[{{Q}_{2}}={{Q}_{3}}\]
C. \[{{Q}_{1}}={{Q}_{3}}\]
D. All the expressions are different
Answer» D. All the expressions are different
376.

The shortest distance between the lines \[{{\mathbf{r}}_{1}}=4\mathbf{i}-3\mathbf{j}-\mathbf{k}+\lambda (\mathbf{i}-4\mathbf{j}+7\mathbf{k})\]            and \[{{\mathbf{r}}_{2}}=\mathbf{i}-\mathbf{j}-10\mathbf{k}+\lambda (2\mathbf{i}-3\mathbf{j}+8\mathbf{k})\]is [J & K 2005]

A. 3
B. 1
C. 2
D. 0
Answer» E.
377.

The mean of five numbers is 30. If one number is excluded, their mean becomes 28. The excluded number is

A. 28
B. 30
C. 35
D. 38
Answer» E.
378.

Let \[P=\{(x,y):\left| {{x}^{2}}+{{y}^{2}} \right|=1,x,y\in R\}.\] Then P is

A. Reflexive
B. Symmetric
C. Transitive
D. Anti-symmetric
Answer» C. Transitive
379.

The area between the parabola \[y={{x}^{2}}\] and the line \[y=x\] is                                                     [UPSEAT 2004]

A. \[\frac{1}{6}\]sq. unit
B. \[\frac{1}{3}\]sq. unit
C. \[\frac{1}{2}\]sq. unit
D. None of these
Answer» B. \[\frac{1}{3}\]sq. unit
380.

If \[\cos \theta +\sec \theta =\frac{5}{2}\], then the general value of \[\theta \]is

A. \[n\pi \pm \frac{\pi }{3}\]
B. \[2n\pi \pm \frac{\pi }{6}\]
C. \[n\pi \pm \frac{\pi }{6}\]
D. \[2n\pi \pm \frac{\pi }{3}\]
Answer» E.
381.

The remainder when \[{{5}^{4n}}\] is divided by 13, is

A. 1
B. 8
C. 9
D. 10
Answer» B. 8
382.

If the mean deviation of the numbers \[1,\,\,1+d,\] \[1+2d,...1+100d\] from their mean is 255, then d is equal to:

A. 20
B. 10.1
C. 20.2
D. 10
Answer» C. 20.2
383.

Let f and g be functions from R To R defined as \[f(x)=\left\{ \begin{matrix}    7{{x}^{2}}+x-8,x\le 1  \\    4x+5,17  \\ \end{matrix},g(x)=\left\{ \begin{matrix}    \left| x \right|,x<-3  \\    0,-3\le x<2  \\    {{x}^{2}}+4,x\ge 2  \\ \end{matrix} \right. \right.\] Then

A. \[(fog)(-3)=8\]
B. \[(fog)(9)=683\]
C. \[(gof)(0)=-8\]
D. \[(gof)(6)=427\]
Answer» C. \[(gof)(0)=-8\]
384.

\[f(x)=\left| x-1 \right|,f:{{R}^{+}}\to R\] and \[g(x)={{e}^{x}},\] \[g:[(-1,\infty )\to R].\] If the function fog (x) is defined, then its domain and range respectively are

A. \[(0,\infty )\,\,and\,\,[0,\infty )\]
B. \[[-1,\infty )\,\,and\,\,[0,\infty )\]
C. \[[-1,\infty )and\left[ 1-\frac{1}{e},\infty  \right)\]
D. \[[-1,\infty )and\left[ \frac{1}{e}-1,\infty  \right)\]
Answer» C. \[[-1,\infty )and\left[ 1-\frac{1}{e},\infty  \right)\]
385.

If the system of equation\[3x-2y+z=0\], \[\lambda x-14y+15z=0\], \[x+2y+3z=0\]have a non-trivial solution, then \[\lambda =\] [EAMCET 1993]

A. 5
B. -5
C. -29
D. 29
Answer» E.
386.

If \[\tan x=\frac{b}{a},\]then \[\sqrt{\frac{a+b}{a-b}}+\sqrt{\frac{a-b}{a+b}}=\] [MP PET 1990, 2002]

A. \[\frac{2\sin x}{\sqrt{\sin 2x}}\]
B. \[\frac{2\cos x}{\sqrt{\cos 2x}}\]
C. \[\frac{2\cos x}{\sqrt{\sin 2x}}\]
D. \[\frac{2\sin x}{\sqrt{\cos 2x}}\]
Answer» C. \[\frac{2\cos x}{\sqrt{\sin 2x}}\]
387.

The matrix \[A=\left[ \begin{matrix}    i & 1-2i  \\    -1-2i & 0  \\ \end{matrix} \right]\]is which of the following   [Kurukshetra CEE 2002]

A. Symmetric
B. Skew-symmetric
C. Hermitian
D. Skew-hermitian
Answer» E.
388.

The number of real values of x for which the equality \[\left| \,3{{x}^{2}}+12x+6\, \right|=5x+16\] holds good is [AMU 1999]

A. 4
B. 3
C. 2
D. 1
Answer» D. 1
389.

Let\[\frac{d}{dx}F(x)=\left( \frac{{{e}^{\sin x}}}{x} \right)\,;\,x>0\]. If \[\int_{\,1}^{\,4}{\frac{3}{x}{{e}^{\sin {{x}^{3}}}}dx=F(k)-F(1)}\], then one of the possible value of k, is               [AIEEE 2003]

A. 15
B. 16
C. 63
D. 64
Answer» E.
390.

The number of different words which can be formed from the letters of the word LUCKNOW when the vowels always occupy even places in

A. 120
B. 720
C. 400
D. None of these
Answer» C. 400
391.

The general solution of the differential equation \[\frac{dy}{dx}=\cot x\cot y\] is        [AISSE 1983; MP PET 1994]

A. \[\cos x=c\,\cos \text{ec}y\]
B. \[\sin x=c\sec y\]
C. \[\sin x=c\cos y\]
D. \[\cos x=c\sin y\]
Answer» C. \[\sin x=c\cos y\]
392.

\[\frac{1}{4}\left[ \sqrt{3}\cos 23{}^\circ -\sin 23{}^\circ  \right]=\]

A. \[\cos 43{}^\circ \]
B. \[\cos 7{}^\circ \]
C. \[\cos 53{}^\circ \]
D. None of these
Answer» E.
393.

How many numbers with no more than three digits can be formed using only the digits 1 through 7 with no digit used more than once in a given number?

A. 259
B. 249
C. 257
D. 252
Answer» B. 249
394.

If \[A,B,C\]are three \[n\times n\]matrices, then \[(ABC{)}'=\] [MP PET 1988]

A. \[{A}'\,{B}'\,{C}'\]
B. \[{C}'\,{B}'\,{A}'\]
C. \[{B}'\,{C}'\,{A}'\]
D. \[{B}'\,{A}'\,{C}'\]
Answer» C. \[{B}'\,{C}'\,{A}'\]
395.

If \[a>2b>0\]then the positive value of m for which \[y=mx-b\sqrt{1+{{m}^{2}}}\]is a common tangent to \[{{x}^{2}}+{{y}^{2}}={{b}^{2}}\]and \[{{(x-a)}^{2}}+{{y}^{2}}={{b}^{2}}\], is            [IIT Screening 2002]

A. \[\frac{2b}{\sqrt{{{a}^{2}}-4{{b}^{2}}}}\]
B. \[\frac{\sqrt{{{a}^{2}}-4{{b}^{2}}}}{2b}\]
C. \[\frac{2b}{a-2b}\]
D. \[\frac{b}{a-2b}\]
Answer» B. \[\frac{\sqrt{{{a}^{2}}-4{{b}^{2}}}}{2b}\]
396.

The equation of a circle that intersects the circle \[{{x}^{2}}+{{y}^{2}}+14x+6y+2=0\]orthogonally and whose centre is (0, 2) is [MP PET 1998]

A. \[{{x}^{2}}+{{y}^{2}}-4y-6=0\]
B. \[{{x}^{2}}+{{y}^{2}}+4y-14=0\]
C. \[{{x}^{2}}+{{y}^{2}}+4y+14=0\]
D. \[{{x}^{2}}+{{y}^{2}}-4y-14=0\]
Answer» E.
397.

The combined equation of the pair of lines through the point (1, 0) and parallel to the lines represented by \[2{{x}^{2}}-xy-{{y}^{2}}=0\] is

A. \[2{{x}^{2}}-xy-{{y}^{2}}-4x-y=0\]
B. \[2{{x}^{2}}-xy-{{y}^{2}}-4x+y+2=0\]
C. \[2{{x}^{2}}+xy+{{y}^{2}}-2x+y=0\]
D. None of these
Answer» C. \[2{{x}^{2}}+xy+{{y}^{2}}-2x+y=0\]
398.

If \[{{\log }_{10}}2,\,{{\log }_{10}}({{2}^{x}}-1)\] and \[{{\log }_{10}}({{2}^{x}}+3)\] are three consecutive terms of an A.P, then the value of x is

A. 1
B. \[lo{{g}_{5}}2\]
C. \[lo{{g}_{2}}5\]
D. \[lo{{g}_{10}}5\]
Answer» D. \[lo{{g}_{10}}5\]
399.

Solution of \[\frac{dy}{dx}=\frac{x\log {{x}^{2}}+x}{\sin y+y\,\,\cos y}\] is           [EAMCET 2003]

A. \[y\sin y={{x}^{2}}\log x+c\]
B. \[y\sin y={{x}^{2}}+c\]
C. \[y\sin y={{x}^{2}}+\log x+c\]
D. \[y\sin y=x\log x+c\]
Answer» B. \[y\sin y={{x}^{2}}+c\]
400.

The solution of \[\cos (x+y)\,dy=\,\,dx\] is         [DCE 1999]

A. \[y=\tan \,\left( \frac{x+y}{2} \right)+c\]
B. \[y+{{\cos }^{-1}}\left( \frac{y}{x} \right)=c\]
C. \[y=x\,\,\sec \left( \frac{y}{x} \right)+c\]
D. None of these
Answer» B. \[y+{{\cos }^{-1}}\left( \frac{y}{x} \right)=c\]