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.

7501.

One root of the equation \[\cos x-x+\frac{1}{2}=0\]lies in the interval [Kurukshetra CEE 1996]

A. \[\left[ 0,\,\frac{\pi }{2} \right]\]
B. \[\left[ -\frac{\pi }{2},\,0 \right]\]
C. \[\left[ \frac{\pi }{2},\,\pi \right]\]
D. \[\left[ \pi ,\frac{3\pi }{2} \right]\]
Answer» B. \[\left[ -\frac{\pi }{2},\,0 \right]\]
7502.

The equation \[\sin x\cos x=2\]has

A. One solution
B. Two solutions
C. Infinite solutions
D. No solutions
Answer» E.
7503.

If \[{{\sin }^{2}}\theta -2\cos \theta +\frac{1}{4}=0,\]then the general value of \[\theta \]is [MP PET 1984]

A. \[n\pi \pm \frac{\pi }{3}\]
B. \[2n\pi \pm \frac{\pi }{3}\]
C. \[2n\pi \pm \frac{\pi }{6}\]
D. \[n\pi \pm \frac{\pi }{6}\]
Answer» C. \[2n\pi \pm \frac{\pi }{6}\]
7504.

If \[2{{\cos }^{2}}x+3\sin x-3=0,\,\,0\le x\le {{180}^{o}}\], then x = [MP PET 1986]

A. \[{{30}^{o}},{{90}^{o}},{{150}^{o}}\]
B. \[{{60}^{o}},{{120}^{o}},{{180}^{o}}\]
C. \[{{0}^{o}},{{30}^{o}},{{150}^{o}}\]
D. \[{{45}^{o}},{{90}^{o}},{{135}^{o}}\]
Answer» B. \[{{60}^{o}},{{120}^{o}},{{180}^{o}}\]
7505.

The solution of the equation \[\left| \,\begin{matrix} \cos \theta & \sin \theta & \cos \theta \\ -\sin \theta & \cos \theta & \sin \theta \\ -\cos \theta & -\sin \theta & \cos \theta \\ \end{matrix}\, \right|=0\], is [AMU 2002]

A. \[\theta =n\pi \]
B. \[\theta =2n\pi \pm \frac{\pi }{2}\]
C. \[\theta =n\pi \pm {{(-1)}^{n}}\frac{\pi }{4}\]
D. \[\theta =2n\pi \pm \frac{\pi }{4}\]
Answer» C. \[\theta =n\pi \pm {{(-1)}^{n}}\frac{\pi }{4}\]
7506.

If \[\sin 2\theta =\cos 3\theta \]and \[\theta \]is an acute angle, then \[\sin \theta \]is equal to [EAMCET 1980]

A. \[\frac{\sqrt{5}-1}{4}\]
B. \[\frac{-\sqrt{5}-1}{4}\]
C. 0
D. None of these
Answer» B. \[\frac{-\sqrt{5}-1}{4}\]
7507.

The general value \[\theta \] is obtained from the equation \[\cos 2\theta =\sin \alpha ,\] is [MP PET 1996]

A. \[2\theta =\frac{\pi }{2}-\alpha \]
B. \[\theta =2n\pi \pm \left( \frac{\pi }{2}-\alpha \right)\]
C. \[\theta =\frac{n\pi +{{(-1)}^{n}}\alpha }{2}\]
D. \[\theta =n\pi \pm \left( \frac{\pi }{4}-\frac{\alpha }{2} \right)\]
Answer» E.
7508.

The solution of the equation \[4{{\cos }^{2}}x+6\]\[{{\sin }^{2}}x=5\] [AI CBSE 1983]

A. \[x=n\pi \pm \frac{\pi }{2}\]
B. \[x=n\pi \pm \frac{\pi }{4}\]
C. \[x=n\pi \pm \frac{3\pi }{2}\]
D. None of these
Answer» C. \[x=n\pi \pm \frac{3\pi }{2}\]
7509.

If cot \[(\alpha +\beta )=0,\]then \[\sin (\alpha +2\beta )=\] [Kerala (Engg.) 2001]

A. \[\sin \alpha \]
B. \[\cos \alpha \]
C. \[\sin \beta \]
D. \[\cos 2\beta \]
Answer» B. \[\cos \alpha \]
7510.

If \[\sin \theta +\cos \theta =\sqrt{2}\cos \alpha \], then the general value of \[\theta \] is

A. \[2n\pi -\frac{\pi }{4}\pm \,\,\alpha \]
B. \[2n\pi +\frac{\pi }{4}\pm \alpha \]
C. \[n\pi -\frac{\pi }{4}\pm \alpha \]
D. \[n\pi +\frac{\pi }{4}\pm \alpha \]
Answer» C. \[n\pi -\frac{\pi }{4}\pm \alpha \]
7511.

If \[12{{\cot }^{2}}\theta -31\,\text{cosec }\theta +\text{32}=\text{0}\], then the value of \[\sin \theta \] is [Karnataka CET 2005]

A. \[\frac{3}{5}\] or 1
B. \[-\sin (B+2C)=\frac{1}{2}\] or \[\frac{-2}{3}\]
C. \[\frac{4}{5}\] or \[\frac{3}{4}\]
D. \[\pm \frac{1}{2}\]
Answer» D. \[\pm \frac{1}{2}\]
7512.

If \[\sqrt{3}\tan 2\theta +\sqrt{3}\tan 3\theta +\tan 2\theta \tan 3\theta =1\], then the general value of\[\theta \]is

A. \[n\pi +\frac{\pi }{5}\]
B. \[\left( n+\frac{1}{6} \right)\frac{\pi }{5}\]
C. \[\left( 2n\pm \frac{1}{6} \right)\frac{\pi }{5}\]
D. \[\left( n+\frac{1}{3} \right)\frac{\pi }{5}\]
Answer» C. \[\left( 2n\pm \frac{1}{6} \right)\frac{\pi }{5}\]
7513.

If in any \[\Delta ABC\], \[\cot \frac{A}{2},\cot \frac{B}{2},\cos \frac{C}{2}\]are in A. P. then [MP PET 2003]

A. \[\cot \frac{A}{2}\cot \frac{B}{2}=4\]
B. \[\cot \frac{A}{2}\cot \frac{C}{2}=3\]
C. \[\cot \frac{B}{2}\cot \frac{C}{2}=1\]
D. \[\cot \frac{B}{2}\tan \frac{C}{2}=0\]
Answer» B. \[\cot \frac{A}{2}\cot \frac{C}{2}=3\]
7514.

The number of triangles ABC that can be formed with \[a=3,b=8\] and \[\sin A=\frac{5}{13}\]is [Roorkee Qualifying 1998]

A. 0
B. 1
C. 2
D. 3
Answer» B. 1
7515.

If angles of a triangle are in the ratio of 2 : 3: 7, then the sides are in the ratio of [MP PET 1996]

A. \[\sqrt{2}:2:(\sqrt{3}+1)\]
B. \[2:\sqrt{2}:(\sqrt{3}+1)\]
C. \[\sqrt{2}:(\sqrt{3}+1):2\]
D. \[2:(\sqrt{3}+1):\sqrt{2}\]
Answer» B. \[2:\sqrt{2}:(\sqrt{3}+1)\]
7516.

In a \[\Delta ABC\], if \[A={{30}^{o}}\]\[b=2,c=\sqrt{3}+1\], then \[\frac{C-B}{2}=\]

A. \[{{15}^{o}}\]
B. \[{{30}^{o}}\]
C. \[{{45}^{o}}\]
D. None of these
Answer» C. \[{{45}^{o}}\]
7517.

The sides of a triangle are three consecutive natural numbers and its largest angle is twice the smallest one. Then the sides of the triangle are

A. 1, 2, 3
B. 2, 3, 4
C. 3, 4, 5
D. 4, 5, 6
Answer» E.
7518.

If \[A={{30}^{o}},a=7,b=8\]in \[\Delta ABC\], then B has

A. One solution
B. Two solutions
C. No solution
D. None of these
Answer» C. No solution
7519.

In \[\Delta ABC,\frac{\sin B}{\sin (A+B)}=\] [MP PET 1989]

A. \[\frac{b}{a+b}\]
B. \[\frac{b}{c}\]
C. \[\frac{c}{b}\]
D. None of these
Answer» C. \[\frac{c}{b}\]
7520.

In a triangle \[ABC\], if \[B=3C\], then the values of \[\sqrt{\left( \frac{b+c}{4c} \right)}\] and \[\left( \frac{b-c}{2c} \right)\] are

A. \[\sin C,\sin \frac{A}{2}\]
B. \[\cos C,\sin \frac{A}{2}\]
C. \[\sin C,\cos \frac{A}{2}\]
D. None of these
Answer» C. \[\sin C,\cos \frac{A}{2}\]
7521.

If \[a=9,b=8\]and \[c=x\]satisfies \[3\cos C=2,\]then [MP PET 1984]

A. \[x=5\]
B. \[x=6\]
C. \[x=4\]
D. \[x=7\]
Answer» E.
7522.

In a \[\Delta ABC\], if \[\angle C={{30}^{o}}\], \[a=47cm\]and \[b=94\]cm, then the triangle is [MP PET 1986]

A. Right angled
B. Right angled isosceles
C. Isosceles
D. Obtuse angled
Answer» E.
7523.

In \[\Delta ABC\], \[{{a}^{2}}({{\cos }^{2}}B-{{\cos }^{2}}C)+\] \[{{b}^{2}}({{\cos }^{2}}C-{{\cos }^{2}}A)+\] \[{{c}^{2}}({{\cos }^{2}}A-{{\cos }^{2}}B)=\]

A. 0
B. 1
C. \[{{a}^{2}}+{{b}^{2}}+{{c}^{2}}\]
D. \[2({{a}^{2}}+{{b}^{2}}+{{c}^{2}})\]
Answer» B. 1
7524.

In a triangle ABC, \[{{a}^{3}}\cos (B-C)+{{b}^{3}}\cos (C-A)+{{c}^{3}}\cos (A-B)=\] [Kerala (Engg.) 2002]

A. \[abc\]
B. \[3abc\]
C. \[a+b+c\]
D. None of these
Answer» C. \[a+b+c\]
7525.

If \[\tan \frac{B-C}{2}=x\cot \frac{A}{2},\]then \[x=\] [MP PET 1992, 2002]

A. \[\frac{c-a}{c+a}\]
B. \[\frac{a-b}{a+b}\]
C. \[\frac{b-c}{b+c}\]
D. None of these
Answer» D. None of these
7526.

In \[\Delta ABC,\] if \[(a+b+c)(a-b+c)\]=3ac, then [AMU 1996]

A. \[\angle B={{60}^{o}}\]
B. \[\angle B={{30}^{o}}\]
C. \[\angle C={{60}^{o}}\]
D. \[\angle A+\angle C={{90}^{o}}\]
Answer» B. \[\angle B={{30}^{o}}\]
7527.

In a \[\Delta ABC,\]if \[\frac{\sin A}{\sin C}=\frac{\sin (A-B)}{\sin (B-C)},\]then \[{{a}^{2}},\ {{b}^{2}},\ {{c}^{2}}\] are in [Pb. CET 2001; Karnataka CET 1999]

A. A.P.
B. G.P.
C. H.P.
D. None of these
Answer» B. G.P.
7528.

In a \[\Delta ABC\] if the sides are \[a=3,\,b=5\] and \[c=4\], then \[\sin \frac{B}{2}+\cos \frac{B}{2}\] is equal to [Karnataka CET 2005]

A. \[\sqrt{2}\]
B. \[\frac{\sqrt{3}+1}{2}\]
C. \[\frac{\sqrt{3}-1}{2}\]
D. 1
Answer» B. \[\frac{\sqrt{3}+1}{2}\]
7529.

The sides of triangle are \[3x+4y,\ 4x+3y\]and \[5x+5y\]units, where \[x,\ y>0.\]The triangle is [AIEEE 2002]

A. Right angled
B. Equilateral
C. Obtuse angled
D. None of these
Answer» D. None of these
7530.

In any triangle ABC, the value of \[a({{b}^{2}}+{{c}^{2}})\cos A+b({{c}^{2}}+{{a}^{2}})\cos B+c({{a}^{2}}+{{b}^{2}})\cos C\]is [MP PET 1994]

A. \[3ab{{c}^{2}}\]
B. \[3{{a}^{2}}bc\]
C. \[3abc\]
D. \[3a{{b}^{2}}c\]
Answer» D. \[3a{{b}^{2}}c\]
7531.

If in a triangle ABC the sides \[AB\]and AC are perpendicular, then the true equation is

A. \[\tan A+\tan B=0\]
B. \[\tan B+\tan C=0\]
C. \[\tan A+2\tan C=0\]
D. \[\tan B.\tan C=1\]
Answer» E.
7532.

In \[\Delta ABC,\]if \[{{\sin }^{2}}\frac{A}{2},{{\sin }^{2}}\frac{B}{2},{{\sin }^{2}}\frac{C}{2}\] be in H. P. then a, b, c will be in

A. A. P.
B. G. P.
C. H. P.
D. None of these
Answer» D. None of these
7533.

In any \[\Delta ABC\]if \[a\cos B=b\cos A\], then the triangle is [MP PET 1984]

A. Equilateral triangle
B. Isosceles triangle
C. Scalene
D. Right angled
Answer» C. Scalene
7534.

In \[\Delta ABC\] if \[a=2,b=4\]and \[\angle C={{60}^{o}}\], then \[\angle A\]and \[\angle B\] are equal to

A. \[{{90}^{o}},{{30}^{o}}\]
B. \[{{60}^{o}},{{60}^{o}}\]
C. \[{{30}^{o}},{{90}^{o}}\]
D. \[{{60}^{o}},{{45}^{o}}\]
Answer» D. \[{{60}^{o}},{{45}^{o}}\]
7535.

Let D be the middle point of the side BC of a triangle ABC. If the triangle ADC is equilateral, then \[{{a}^{2}}:{{b}^{2}}:{{c}^{2}}\]is equal to [Pb. CET 2004]

A. \[1:4:3\]
B. \[4:1:3\]
C. \[4:3:1\]
D. \[3:4:1\]
Answer» C. \[4:3:1\]
7536.

The period of \[{{\sin }^{4}}x+{{\cos }^{4}}x\]is [RPET 1997]

A. \[\pi /2\]
B. \[\pi \]
C. \[2\pi \]
D. \[3\pi /2\]
Answer» B. \[\pi \]
7537.

Period of \[\cos (7x-5)\]is

A. \[\frac{2\pi -5}{7}\]
B. \[2\pi -5\]
C. \[\frac{2\pi }{7}\]
D. \[\frac{\pi }{7}\]
Answer» D. \[\frac{\pi }{7}\]
7538.

Which of the following functions has period \[2\pi \] [Pb. CET 2004]

A. \[y=\sin \left( 2\pi t+\frac{\pi }{3} \right)+\]\[2\sin \left( 3\pi t+\frac{\pi }{4} \right)+3\sin 5\pi t\]
B. \[y=\sin \frac{\pi }{3}t+\sin \frac{\pi }{4}t\]
C. \[y=\sin t+\cos 2t\]
D. None of these
Answer» D. None of these
7539.

The angular depressions of the top and the foot of a chimney as seen from the top of a second chimney, which is 150 m high and standing on the same level as the first are \[\theta \] and \[\varphi \] respectively, then the distance between their tops when \[\tan \theta =\frac{4}{3}\]and \[\tan \varphi =\frac{5}{2}\], is [Pb. CET 2004; IIT 1965]

A. \[\frac{150}{\sqrt{3}}metres\]
B. \[100\sqrt{3}metres\]
C. \[150metres\]
D. \[100metres\]
Answer» E.
7540.

A person observes the angle of elevation of a building as 30°. The person proceeds towards the building with a speed of \[25(\sqrt{3}-1)m/hour.\]After \[2\,hours\], he observes the angle of elevation as 45°. The height of the building (in meter) is [UPSEAT 2003]

A. 100
B. 50
C. \[50(\sqrt{3}+1)\]
D. \[50(\sqrt{3}-1)\]
Answer» C. \[50(\sqrt{3}+1)\]
7541.

A tower subtends an angle \[\alpha \]at a point A in the plane of its base and the angle of depression of the foot of the tower at a point l meters just above A is\[\beta \]. The height of the tower is

A. \[l\tan \beta \cot \alpha \]
B. \[l\tan \alpha \cot \beta \]
C. \[l\tan \alpha \tan \beta \]
D. \[l\cot \alpha \cot \beta \]
Answer» C. \[l\tan \alpha \tan \beta \]
7542.

The top of a hill when observed form the top and bottom of a building of height h is at angles of elevation p and q respectively. What is the height of the hill?

A. \[\frac{h\cot q}{\cot q-\cot p}\]
B. \[\frac{h\cot p}{\cot p-\cot q}\]
C. \[\frac{2h\tan p}{\tan p-\tan q}\]
D. \[\frac{2h\tan q}{\tan q-\tan p}\]
Answer» C. \[\frac{2h\tan p}{\tan p-\tan q}\]
7543.

If \[A+B+C=\pi ,\] then\[\cos 2A+\cos 2B+\cos 2C+4\sin A\sin B\sin C\] is equal to:

A. 0
B. 1
C. 2
D. 3
Answer» C. 2
7544.

If the angles of a triangle are \[30{}^\circ \] and \[45{}^\circ \] and the included side is \[(\sqrt{3}+1),\] then what is the area of the triangle?

A. \[\frac{\sqrt{3}+1}{2}\]
B. \[2(\sqrt{3}+1)\]
C. \[\frac{\sqrt{3}+1}{3}\]
D. \[\frac{\sqrt{3}-1}{2}\]
Answer» B. \[2(\sqrt{3}+1)\]
7545.

Angles of a triangle are in the ratio \[4:1:1.\] The ratio between its greatest side and perimeter is

A. \[\frac{3}{2+\sqrt{3}}\]
B. \[\frac{1}{2+\sqrt{3}}\]
C. \[\frac{\sqrt{3}}{\sqrt{3}+2}\]
D. \[\frac{2}{2+\sqrt{3}}\]
Answer» D. \[\frac{2}{2+\sqrt{3}}\]
7546.

In a \[\Delta ABC,\]\[\frac{\sin A}{\sin C}=\frac{\sin (A-B)}{\sin (B-C)},\] then \[{{a}^{2}},{{b}^{2}},{{c}^{2}}\] are such that

A. \[{{b}^{2}}=ac\]
B. \[{{b}^{2}}=\frac{{{a}^{2}}{{c}^{2}}}{{{a}^{2}}+{{c}^{2}}}\]
C. They are in A.P.
D. \[{{b}^{2}}={{a}^{2}}+{{c}^{2}}\]
Answer» D. \[{{b}^{2}}={{a}^{2}}+{{c}^{2}}\]
7547.

If the co-ordinates of the points \[A,B,C\]be \[(-1,\,3,\,2),\,\,(2,\,3,\,5)\] and (3, 5,?2) respectively, then \[\angle A=\]

A. \[0{}^\circ \]
B. \[45{}^\circ \]
C. \[60{}^\circ \]
D. \[90{}^\circ \]
Answer» E.
7548.

The co-ordinates of points \[A,B,C,D\]are (a, 2, 1), (1, ?1, 1), (2, ? 3, 4) and (a+1, a+2, a+3) respectively. If \[AB=5\]and \[CD=6\], then \[a=\]

A. 2
B. 3
C. ? 2
D. ? 3
Answer» E.
7549.

The projection of a line on a co-ordinate axes are 2, 3, 6. Then the length of the line is [Orissa JEE 2002]

A. 7
B. 5
C. 1
D. 11
Answer» B. 5
7550.

If \[A(1,\,2,\,3),\,B(-1,-1,-1)\] be the points, then the distance AB is [MP PET 2001; Pb. CET 2001]

A. \[\sqrt{5}\]
B. \[\sqrt{21}\]
C. \[\sqrt{29}\]
D. None of these
Answer» D. None of these