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.

1751.

If \[R\subset A\times B\] and \[S\subset B\times C\,\] be two relations, then \[{{(SoR)}^{-1}}=\]

A. \[{{S}^{-1}}o{{R}^{-1}}\]
B. \[{{R}^{-1}}o{{S}^{-1}}\]
C. \[SoR\]
D. \[RoS\]
Answer» C. \[SoR\]
1752.

Let X be a family of sets and R be a relation on X defined by 'A is disjoint from B'. Then R is

A. Reflexive
B. Symmetric
C.  Anti-symmetric
D. Transitive
Answer» C.  Anti-symmetric
1753.

For real numbers x and y, we write \[x\,R\,y\Leftrightarrow \] \[x-y+\sqrt{2}\] is an irrational number. Then the relation R  is

A. Reflexive
B. Symmetric
C. Transitive
D. None of these
Answer» B. Symmetric
1754.

Let A = {1, 2, 3}. The total number of distinct relations that can be defined over A is

A. \[{{2}^{9}}\]
B. 6
C. 8
D. None of these
Answer» B. 6
1755.

In a \[\Delta ABC,\]if \[\frac{b+c}{11}=\frac{c+a}{12}=\frac{a+b}{13}\], then \[\cos C=\] [Karnataka CET 2003]

A. \[\frac{7}{5}\]
B. \[\frac{5}{7}\]
C. \[\frac{17}{36}\]
D. \[\frac{16}{17}\]
Answer» C. \[\frac{17}{36}\]
1756.

The smallest angle of the \[\Delta ABC\], when \[a=7,b=4\sqrt{3}\]and \[c=\sqrt{13},\] is [MP PET 2003]

A. \[{{30}^{o}}\]
B. \[{{15}^{o}}\]
C. \[{{45}^{o}}\]
D. None of these
Answer» B. \[{{15}^{o}}\]
1757.

If the angles of a triangle are in the ratio 4:1:1, then the ratio of the longest side to the perimeter is    [IIT Screening 2003]

A. \[\sqrt{3}:(2+\sqrt{3})\]
B. \[1:6\]
C. \[1:(2+\sqrt{3})\]
D. \[2:3\]
Answer» B. \[1:6\]
1758.

In any triangle \[AB=2,BC=4,CA=3\]and D is mid point of BC, then [Roorkee 1995]

A. \[\cos B=\frac{11}{6}\]
B. \[\cos B=\frac{7}{8}\]
C. \[AD=2.4\]
D. \[A{{D}^{2}}=2.5\]
Answer» E.
1759.

In a \[\Delta ABC,\,\,\frac{\cos C+\cos A}{c+a}+\frac{\cos B}{b}\]is equal to [EAMCET 2001]

A. \[\frac{1}{a}\]
B. \[\frac{1}{b}\]
C. \[\frac{1}{c}\]
D. \[\frac{c+a}{b}\]
Answer» C. \[\frac{1}{c}\]
1760.

In a \[\Delta ABC,\] \[A:B:C\]. Then \[[a+b+c\sqrt{2}]\] is equal to [DCE 2001]

A. 2b
B. 2c
C. 3b
D. 3a
Answer» D. 3a
1761.

In a triangle \[ABC\], right angled at C, the value of \[\tan A+\tan B\] is [Pb. CET 1990; Karnataka CET 1999; MP PET 2001]

A. \[a+b\]
B. \[\frac{{{a}^{2}}}{bc}\]
C. \[\frac{{{b}^{2}}}{ac}\]
D. \[\frac{{{c}^{2}}}{ab}\]
Answer» E.
1762.

In a \[\Delta ABC,\]\[2a\sin \,\,\left( \frac{A-B+C}{2} \right)\] is equal to  [IIT Screening 2000]

A. \[{{a}^{2}}+{{b}^{2}}-{{c}^{2}}\]
B. \[{{c}^{2}}+{{a}^{2}}-{{b}^{2}}\]
C. \[{{b}^{2}}-{{c}^{2}}-{{a}^{2}}\]
D. \[{{c}^{2}}-{{a}^{2}}-{{b}^{2}}\]
Answer» C. \[{{b}^{2}}-{{c}^{2}}-{{a}^{2}}\]
1763.

In a \[\Delta ABC\], if  \[{{c}^{2}}+{{a}^{2}}-{{b}^{2}}=ac\], then \[\angle B=\] [MP PET 1983, 89, 90]

A. \[\frac{\pi }{6}\]
B. \[\frac{\pi }{4}\]
C. \[\frac{\pi }{3}\]
D. None of these
Answer» D. None of these
1764.

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
1765.

If in a triangle ABC, angle C is \[{{45}^{o}}\], then \[(1+\cot A)(1+\cot B)=\]     [Kurukshetra CEE 1998]

A. -1
B. 2
C. 3
D. \[1/\sqrt{2}\]
Answer» C. 3
1766.

If the lengths of the sides of a triangle are 3, 5, 7, then the largest angle of the triangle is  [IIT Screening 1994; Kerala (Engg.) 2002]

A. \[\pi /2\]
B. \[5\pi /6\]
C. \[2\pi /3\]
D. \[3\pi /4\]
Answer» D. \[3\pi /4\]
1767.

If in a right angled triangle the hypotenuse is four times as long as the perpendicular drawn to it from opposite vertex, then one of its acute angle is   [MP PET 1998, 2004; UPSEAT 2002]

A. \[{{15}^{o}}\]
B. \[{{30}^{o}}\]
C. \[{{45}^{o}}\]
D. None of these
Answer» B. \[{{30}^{o}}\]
1768.

If in a triangle ABC side \[a=(\sqrt{3}+1)\]cms and \[\angle B={{30}^{o}},\] \[\angle C={{45}^{o}}\], then the area of the triangle is  [MP PET 1997]

A. \[\frac{\sqrt{3}+1}{3}c{{m}^{2}}\]
B. \[\frac{\sqrt{3}+1}{2}c{{m}^{2}}\]
C. \[\frac{\sqrt{3}+1}{2\sqrt{2}}c{{m}^{2}}\]
D. \[\frac{\sqrt{3}+1}{3\sqrt{2}}c{{m}^{2}}\]
Answer» C. \[\frac{\sqrt{3}+1}{2\sqrt{2}}c{{m}^{2}}\]
1769.

In any triangle \[ABC,\frac{\tan \frac{A}{2}-\tan \frac{B}{2}}{\tan \frac{A}{2}+\tan \frac{B}{2}}=\]

A. \[\frac{a-b}{a+b}\]
B. \[\frac{a-b}{c}\]
C. \[\frac{a-b}{a+b+c}\]
D. \[\frac{c}{a+b}\]
Answer» C. \[\frac{a-b}{a+b+c}\]
1770.

Sides of a triangle are \[2cm,\sqrt{6}\,cm\] and \[(\sqrt{3}+1)cm\]. The smallest angle of the triangle is

A. \[{{30}^{o}}\]
B. \[{{45}^{o}}\]
C. \[{{60}^{o}}\]
D. \[{{75}^{o}}\]
Answer» C. \[{{60}^{o}}\]
1771.

If \[A={{30}^{o}},c=7\sqrt{3}\]and \[C={{90}^{o}}\]in \[\Delta ABC\], then a =

A. \[7\sqrt{3}\]
B. \[\frac{7\sqrt{3}}{2}\]
C. \[\frac{7}{2}\]
D. None of these
Answer» C. \[\frac{7}{2}\]
1772.

In a \[\Delta ABC\], if \[{{b}^{2}}+{{c}^{2}}=3{{a}^{2}}\], then \[\cot B+\cot C-\cot A=\] [MP PET 1991]

A. 1
B. \[\frac{ab}{4\Delta }\]
C. 0
D. \[\frac{ac}{4\Delta }\]
Answer» D. \[\frac{ac}{4\Delta }\]
1773.

The smallest angle of the triangle whose sides are \[6+\sqrt{12},\sqrt{48},\sqrt{24}\]is [EAMCET 1985]

A. \[\frac{\pi }{3}\]
B. \[\frac{\pi }{4}\]
C. \[\frac{\pi }{6}\]
D. None of these
Answer» D. None of these
1774.

In a \[\Delta ABC\], \[a=5,b=4\]and \[\cos (A-B)=\frac{31}{32}\], then side c is equal to

A. 6
B. 7
C. 9
D. None of these
Answer» B. 7
1775.

In a \[\Delta ABC\], \[b=2,C={{60}^{o}},c=\sqrt{6}\], then a =

A. \[\sqrt{3}-1\]
B. \[\sqrt{3}\]
C. \[\sqrt{3}+1\]
D. None of these
Answer» D. None of these
1776.

In triangle ABC, \[A={{30}^{o}},b=8,a=6\], then \[B={{\sin }^{-1}}x\], where x = [Karnataka CET 1990]

A. \[\frac{1}{2}\]
B. \[\frac{1}{3}\]
C. \[\frac{2}{3}\]
D. 1
Answer» D. 1
1777.

In a triangle \[ABC\], if \[a=2,B={{60}^{o}}\]and \[C={{75}^{o}}\], then b = [Karnataka CET 1992]

A. \[\sqrt{3}\]
B. \[\sqrt{6}\]
C. \[\sqrt{9}\]
D. \[1+\sqrt{2}\]
Answer» C. \[\sqrt{9}\]
1778.

If in the \[\Delta ABC,AB=2BC\], then \[\tan \frac{B}{2}:\cot \left( \frac{C-A}{2} \right)\]

A. 0.125694444444444
B. 0.0840277777777778
C. 0.0430555555555556
D. 0.04375
Answer» E.
1779.

ABC is a triangle such that \[\sin (2A+B)=\] \[\sin (C-A)=\] \[-\sin (B+2C)=\frac{1}{2}\]. If A, B and C are in A.P., then A, B and C are

A. \[{{30}^{o}},{{60}^{o}},{{90}^{o}}\]
B. \[{{45}^{o}},{{60}^{o}},{{75}^{o}}\]
C. \[{{45}^{o}},{{45}^{o}},{{90}^{o}}\]
D. \[{{60}^{o}},{{60}^{o}},{{60}^{o}}\]
Answer» C. \[{{45}^{o}},{{45}^{o}},{{90}^{o}}\]
1780.

If in a \[\Delta ABC\], \[\cos 3A+\cos 3B+\cos 3C=1\], then one angle must be exactly equal to

A. \[{{90}^{o}}\]
B. \[{{45}^{o}}\]
C. \[{{120}^{o}}\]
D. None of these
Answer» D. None of these
1781.

In \[\Delta ABC,\frac{\sin (A-B)}{\sin (A+B)}=\] [MP PET 1986]

A. \[\frac{{{a}^{2}}-{{b}^{2}}}{{{c}^{2}}}\]
B. \[\frac{{{a}^{2}}+{{b}^{2}}}{{{c}^{2}}}\]
C. \[\frac{{{c}^{2}}}{{{a}^{2}}-{{b}^{2}}}\]
D. \[\frac{{{c}^{2}}}{{{a}^{2}}+{{b}^{2}}}\]
Answer» B. \[\frac{{{a}^{2}}+{{b}^{2}}}{{{c}^{2}}}\]
1782.

Point D, E are taken on the side BC of a triangle \[ABC\]such that \[BD=DE=EC\].If \[\angle BAD=x\], \[\angle DAE=y\], \[\angle EAC=z\], then the value of \[\frac{\sin (x+y)\sin (y+z)}{\sin x\sin z}=\]

A. 1
B. 2
C. 4
D. None of these
Answer» D. None of these
1783.

The perimeter of\[\Delta ABC\]is 6 times the arithmetic mean of the sines of its angles. If the side a is 1, then the angle A is   [IIT Screening 1992; DCE 1999]

A. \[\frac{\pi }{6}\]
B. \[\frac{\pi }{3}\]
C. \[\frac{\pi }{2}\]
D. \[\pi \]
Answer» B. \[\frac{\pi }{3}\]
1784.

If in a triangle \[ABC,\] \[\cos A\cos B+\sin A\sin B\sin C=1,\] then the sides are proportional to

A. 1: 1: \[\sqrt{2}\]
B. \[1:\sqrt{2}:1\]
C. \[\sqrt{2}:1:1\]
D. None of these
Answer» B. \[1:\sqrt{2}:1\]
1785.

If \[{{a}^{2}},{{b}^{2}},{{c}^{2}}\]are in A. P. then which of the following are also in A.P. [ISM Dhandbad 1989]

A. \[\sin A,\sin B,\sin C\]
B. \[\tan A,\tan B,\tan C\]
C. \[\cot A,\cot B,\cot C\]
D. None of these
Answer» D. None of these
1786.

If \[b=3,c=4\]and \[B=\frac{\pi }{3}\], then the number of triangle that can be constructed is               [Roorkee 1992]

A. Infinite
B. Two
C. One
D. Nil
Answer» E.
1787.

If \[a=2,b=3,c=5\]in \[\Delta ABC\], then C =  [EAMCET 1984]

A. \[\frac{\pi }{6}\]
B. \[\frac{\pi }{3}\]
C. \[\frac{\pi }{2}\]
D. None of these
Answer» E.
1788.

In a triangle\[ABC,\]\[a=4,b=3\], \[\angle A={{60}^{o}}\]. Then c is the root of the equation                       [Roorkee 1993]

A. \[{{c}^{2}}-3c-7=0\]
B. \[{{c}^{2}}+3c+7=0\]
C. \[{{c}^{2}}-3c+7=0\]
D. \[{{c}^{2}}+3c-7=0\]
Answer» B. \[{{c}^{2}}+3c+7=0\]
1789.

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. \[\frac{c}{b}\]
1790.

In triangle\[ABC\]if \[A+C=2B\], then \[\frac{a+c}{\sqrt{{{a}^{2}}-ac+{{c}^{2}}}}\]is equal to [UPSEAT 1999]

A. \[2\cos \frac{A-C}{2}\]
B. \[\sin \frac{A+C}{2}\]
C. \[\sin \frac{A}{2}\]
D. None of these
Answer» B. \[\sin \frac{A+C}{2}\]
1791.

Area of the triangle is \[10\sqrt{3}\]sq. cm, angle \[C={{60}^{o}}\]and its perimeter is 20 cm, then side c will be

A. 5
B. 7
C. 8
D. 10
Answer» C. 8
1792.

In a triangle \[ABC\] if \[2{{a}^{2}}{{b}^{2}}+2{{b}^{2}}{{c}^{2}}=\] \[{{a}^{4}}+{{b}^{4}}+{{c}^{4}}\], then angle B is equal to

A. \[{{45}^{o}}\]or \[{{135}^{o}}\]
B. \[{{135}^{o}}\]or \[{{120}^{o}}\]
C. \[{{30}^{o}}\]or \[{{60}^{o}}\]
D. None of these
Answer» B. \[{{135}^{o}}\]or \[{{120}^{o}}\]
1793.

In \[\Delta ABC\], \[(b-c)\cot \frac{A}{2}+(c-a)\cot \frac{B}{2}+(a-b)\]\[\cot \frac{C}{2}\] is equal to [WB JEE 1989]

A. 0
B. 1
C. \[\pm 1\]
D. 2
Answer» B. 1
1794.

If the sides of a triangle are p,q and\[\sqrt{{{p}^{2}}+pq+{{q}^{2}}}\], then the biggest angle is   [Kerala (Engg.) 2005]

A. \[\pi /2\]
B. \[2\pi /3\]
C. \[5\pi /4\]
D. \[7\pi /4\]   
E. \[5\pi /3\]
Answer» C. \[5\pi /4\]
1795.

If the angles \[A,B,C\]of a triangle are in A.P. and the sides \[a,b,c\] opposite to these angles are in G. P. then \[{{a}^{2}},{{b}^{2}},{{c}^{2}}\] are in [MP PET 1998]

A. A. P.
B. H. P.
C. G. P.
D. None of these
Answer» B. H. P.
1796.

In \[\Delta \,ABC\], \[a=2cm,b=3cm\] and \[c=4cm\] , then angle A is [MNR 1973; MP PET 1984, 2002]

A. \[{{\cos }^{-1}}\left( \frac{1}{24} \right)\]
B. \[{{\cos }^{-1}}\left( \frac{11}{16} \right)\]
C. \[{{\cos }^{-1}}\left( \frac{7}{8} \right)\]
D. \[{{\cos }^{-1}}\left( -\frac{1}{4} \right)\]
Answer» C. \[{{\cos }^{-1}}\left( \frac{7}{8} \right)\]
1797.

In triangle \[ABC\], \[(b+c)\cos A+(c+a)\cos B\] \[+(a+b)\cos C=\] [MP PET 1985]

A. 0
B. 1
C. \[a+b+c\]
D. \[2(a+b+c)\]
Answer» D. \[2(a+b+c)\]
1798.

If in a triangle the angles are in A. P. and \[b:c=\sqrt{3}:\sqrt{2}\], then \[\angle A\]is equal to  [IIT 1981; Kurukshetra CEE 1998; Pb. CET 1990]

A. \[{{30}^{o}}\]
B. \[{{60}^{o}}\]
C. \[{{15}^{o}}\]
D. \[{{75}^{o}}\]
Answer» E.
1799.

If in a triangle, \[a{{\cos }^{2}}\frac{C}{2}+c{{\cos }^{2}}\frac{A}{2}=\frac{3b}{2},\]then its sides will be in                     [MP PET 1982; AMU 2000; AIEEE 2003]

A. A. P.
B. G. P.
C. H. P.
D. A. G.
Answer» B. G. P.
1800.

If in a triangle \[ABC\], \[b=\sqrt{3}\], \[c=1\] and \[B-C={{90}^{o}}\]then \[\angle A\] is [MP PET 1983]

A. \[{{30}^{o}}\]
B. \[{{45}^{o}}\]
C. \[{{75}^{o}}\]
D. \[{{15}^{o}}\]
Answer» B. \[{{45}^{o}}\]