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.

4501.

If  \[arg\,(z-a)=\frac{\pi }{4}\], where \[a\in R\],  then the locus of \[z\in C\] is a [MP PET 1997]

A. Hyperbola
B. Parabola
C. Ellipse
D. Straight line
Answer» E.
4502.

If  \[{{\log }_{\sqrt{3}}}\left( \frac{|z{{|}^{2}}-|z|+1}{2+|z|} \right)\]\[

A. \[|z|=5\]
B. \[|z|<5\]
C. \[|z|>5\]
D. None of these
Answer» C. \[|z|>5\]
4503.

The locus represented by \[|z-1|=|z+i|\] is [EAMCET 1991]

A. A circle of radius 1
B. An ellipse with foci at \[(1,\,0)\] and (0, - 1)
C. A straight line through the origin
D. A circle on the line joining \[(1,\,0),(0,\,1)\] as diameter
Answer» D. A circle on the line joining \[(1,\,0),(0,\,1)\] as diameter
4504.

\[R({{z}^{2}})=1\]is represented by

A. The parabola \[{{x}^{2}}+{{y}^{2}}=1\]
B. The hyperbola \[{{x}^{2}}-{{y}^{2}}=1\]
C. Parabola or a circle
D. All the above
Answer» C. Parabola or a circle
4505.

The locus of \[z\] given by \[\left| \frac{z-1}{z-i} \right|=1\],  is [Roorkee 1990]

A. A circle
B. An ellipse
C. A straight line
D. A parabola
Answer» D. A parabola
4506.

A point z moves on Argand diagram in such a way that |z -3i| \[=2,\] then its locus will be   [RPET 1992; MP PET 2002]

A. \[y-\]axis
B. A straight line
C. A circle
D. None of these
Answer» D. None of these
4507.

If \[z=x+iy\] and \[|z-zi|\,=1,\]then [RPET 1988, 91]

A. \[z\]lies on \[x\]-axis
B. \[z\]lies on \[y\]-axis
C. z lies on a circle
D. None of these
Answer» D. None of these
4508.

If  \[z=(\lambda +3)+i\sqrt{5-{{\lambda }^{2}},}\] then the locus of z is a

A. Circle
B. Straight line
C. Parabola
D. None of these
Answer» B. Straight line
4509.

If the imaginary part of \[\frac{2z+1}{iz+1}\]is -2, then the locus of the point representing \[z\]in the complex plane is [DCE 2001]

A. A circle
B. A straight line
C. A parabola
D. None of these
Answer» C. A parabola
4510.

The equation \[\overline{b}z+b\overline{z}=c,\]where \[b\] is a non-zero complex constant and c is real, represents

A. A circle
B.  A straight line
C. A parabola
D. None of these
Answer» C. A parabola
4511.

The region of Argand plane defined by  \[|z-1|\,\,+\,\,|z+1|\,\,\le 4\] is

A. Interior of an ellipse
B. Exterior of a circle
C. Interior and boundary of an ellipse
D. None of these
Answer» D. None of these
4512.

If \[|z+1|\,\,=\sqrt{2}|z-1|,\]then the locus described by the point \[z\] in the Argand diagram is a

A. Straight line
B. Circle
C. Parabola
D. None of these
Answer» C. Parabola
4513.

When \[\frac{z+i}{z+2}\] is purely imaginary, the locus described by the point \[z\] in the Argand diagram is a

A. Circle of radius \[\frac{\sqrt{5}}{2}\]
B. Circle of radius \[\frac{5}{4}\]
C. Straight line
D. Parabola
Answer» B. Circle of radius \[\frac{5}{4}\]
4514.

If \[{{z}_{1}}=1+2i,{{z}_{2}}=2+3i,{{z}_{3}}=3+4i,\] then \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] represent the vertices of a/an [Orissa JEE 2004]

A. Equilateral triangle
B. Isosceles triangle 
C. Right angled triangle
D. None of these
Answer» E.
4515.

The area of the triangle whose vertices are represented by the complex numbers 0, z, \[z{{e}^{i\alpha }},\] \[(0

A. \[\frac{1}{2}|z{{|}^{2}}\cos \alpha \]
B. \[\frac{1}{2}|z{{|}^{2}}\sin \alpha \]
C. \[\frac{1}{2}|z{{|}^{2}}\sin \alpha \cos \alpha \]
D. \[\frac{1}{2}|z{{|}^{2}}\]
Answer» C. \[\frac{1}{2}|z{{|}^{2}}\sin \alpha \cos \alpha \]
4516.

If \[{{z}_{1}}=1+i,\,{{z}_{2}}=-2+3i\,\,\text{and}\,\,\text{ }{{z}_{3}}=ai/3\], where \[{{i}^{2}}=-1,\] are collinear then the value of a is [AMU 2001]

A. -1
B. 3
C. 4
D. 5
Answer» E.
4517.

If the area of the triangle formed by the points \[z,z+iz\] and iz on the complex plane is 18, then the value of \[|z|\] is [MP PET 2001]

A. 6
B. 9
C. \[3\sqrt{2}\]
D. \[2\sqrt{3}\]
Answer» B. 9
4518.

Let \[{{z}_{1}}\] and  \[{{z}_{2}}\] be two complex numbers such that  \[\frac{{{z}_{1}}}{{{z}_{2}}}+\frac{{{z}_{2}}}{{{z}_{1}}}=1\]. Then

A. \[{{z}_{1}},{{z}_{2}}\]are collinear
B. \[{{z}_{1}},{{z}_{2}}\]and the origin form a right angled triangle
C. \[{{z}_{1}},{{z}_{2}}\]and the origin form an equilateral triangle
D. None of these
Answer» D. None of these
4519.

If \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] are affixes of the vertices \[A,B\] and \[C\] respectively of a triangle \[ABC\] having centroid at \[G\] such that \[z=0\] is the mid point of \[AG,\] then

A. \[{{z}_{1}}+{{z}_{2}}+{{z}_{3}}=0\]
B. \[{{z}_{1}}+4{{z}_{2}}+{{z}_{3}}=0\]
C. \[{{z}_{1}}+{{z}_{2}}+4{{z}_{3}}=0\]
D. \[{{z}_{1}}+{{z}_{2}}+{{z}_{3}}=0\]
Answer» E.
4520.

If  \[{{z}_{1}},{{z}_{2}}\in C,\] then [MP PET 1995]

A. \[|{{z}_{1}}+{{z}_{2}}|\,\ge \,|{{z}_{1}}|+|{{z}_{2}}|\]
B. \[|{{z}_{1}}-{{z}_{2}}|\,\ge \,|{{z}_{1}}|+|{{z}_{2}}|\]
C. \[|{{z}_{1}}-{{z}_{2}}|\,\le \left| \,|{{z}_{1}}|-|{{z}_{2}}|\, \right|\]
D. \[|{{z}_{1}}+{{z}_{2}}|\,\ge \left| \,|{{z}_{1}}|-|{{z}_{2}}|\, \right|\]
Answer» E.
4521.

If  A, B, C are represented by \[3+4i,\] \[5-2i\], \[-1+16i\], then A, B, C are [RPET 1986]

A. Collinear
B. Vertices of equilateral triangle
C. Vertices of isosceles triangle
D. Vertices of right angled triangle
Answer» B. Vertices of equilateral triangle
4522.

If \[z=x+iy,\] then area of the triangle whose vertices are points \[z,\,iz\] and \[z+iz\] is [MP PET 1997; IIT 1986; AMU 2000; UPSEAT 2002]

A. \[2|z{{|}^{2}}\]
B. \[\frac{1}{2}|z{{|}^{2}}\]
C. \[|z{{|}^{2}}\]
D. \[\frac{3}{2}|z{{|}^{2}}\]
Answer» C. \[|z{{|}^{2}}\]
4523.

The points \[1+3i,\,5+i\] and \[3+2i\] in the complex plane are [MP PET 1987]

A. Vertices of a right angled triangle
B. Collinear
C. Vertices of an obtuse angled triangle
D. Vertices of an equilateral triangle
Answer» C. Vertices of an obtuse angled triangle
4524.

If z is a complex number in the Argand plane, then the equation \[|z-2|+|z+2|=8\]represents [Orissa JEE 2004]

A. Parabola
B. Ellipse
C. Hyperbola
D. Circle
Answer» C. Hyperbola
4525.

If \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] are three collinear points in argand plane, then \[\left| \,\begin{matrix}    {{z}_{1}} & \overline{{{z}_{1}}} & 1  \\    {{z}_{2}} & \overline{{{z}_{2}}} & 1  \\    {{z}_{3}} & \overline{{{z}_{3}}} & 1  \\ \end{matrix}\, \right|=\] [Orissa JEE 2004]

A. 0
B. -1
C. 1
D. 2
Answer» B. -1
4526.

If P, Q, R, S are represented by the complex numbers \[4+i,\,\,1+6i,\,\,-4+3i,\,\,-1-2i\] respectively, then PQRS is a [Orissa JEE 2003]

A. Rectangle
B. Square
C. Rhombus
D. Parallelogram
Answer» C. Rhombus
4527.

The equation \[z\,\overline{z}+a\,\bar{z}+\bar{a}z+b=0,b\in R\] represents a circle if

A. \[|a{{|}^{2}}=b\]
B. \[|a{{|}^{2}}>b\]
C. \[|a{{|}^{2}}<b\]
D. None of these
Answer» C. \[|a{{|}^{2}}<b\]
4528.

For all complex numbers \[{{z}_{1}},{{z}_{2}}\]  satisfying \[|{{z}_{1}}|\,=12\,\] \[\,\text{and }\,|{{z}_{2}}-3-4i|\,=5,\] the minimum value of \[|{{z}_{1}}-{{z}_{2}}|\] is [IIT Screening 2002]

A. 0
B. 2
C. 7
D. 17
Answer» C. 7
4529.

Let \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] be three vertices of an equilateral triangle circumscribing the circle \[|z|\]=\[\frac{1}{2}\].  If \[{{z}_{1}}=\frac{1}{2}+\frac{\sqrt{3}\,i}{2}\] and \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] are in anticlockwise sense then \[{{z}_{2}}\] is [Orissa JEE 2002]

A. \[1+\sqrt{3}\,i\]
B. \[1-\sqrt{3}\,i\]
C. 1
D. - 1\[\]
Answer» E.
4530.

A circle whose radius is r and centre \[{{z}_{0}}\], then the equation of the circle is [RPET 2000]

A. \[z\bar{z}-z{{\bar{z}}_{0}}-\bar{z}{{z}_{0}}+{{z}_{0}}{{\bar{z}}_{0}}={{r}^{2}}\]
B. \[z\bar{z}+z{{\bar{z}}_{0}}-\bar{z}{{z}_{0}}+{{z}_{0}}{{\bar{z}}_{0}}={{r}^{2}}\]
C. \[z\bar{z}-z{{\bar{z}}_{0}}+\bar{z}{{z}_{0}}-{{z}_{0}}{{\bar{z}}_{0}}={{r}^{2}}\]
D. None of these
Answer» B. \[z\bar{z}+z{{\bar{z}}_{0}}-\bar{z}{{z}_{0}}+{{z}_{0}}{{\bar{z}}_{0}}={{r}^{2}}\]
4531.

In the argand diagram, if O, P and Q represents respectively the origin, the complex numbers z and z +  iz, then the angle \[\angle OPQ\] is [MP PET 2000]

A. \[\frac{\pi }{4}\]
B. \[\frac{\pi }{3}\]
C. \[\frac{\pi }{2}\]
D. \[\frac{2\pi }{3}\]
Answer» D. \[\frac{2\pi }{3}\]
4532.

If centre of a regular hexagon is at origin and one of the vertex on argand diagram is 1 + 2i, then its perimeter is  [RPET 1999]

A. \[2\sqrt{5}\]
B. \[6\sqrt{2}\]
C. \[4\sqrt{5}\]
D. \[6\sqrt{5}\]
Answer» E.
4533.

If \[|z-2|/|z-3|=2\] represents a circle, then its radius is equal to [Kurukshetra CEE 1998]

A. 1
B. \[1/3\]
C. \[3/4\]
D. \[2/3\]
Answer» E.
4534.

If complex numbers \[{{z}_{1}},{{z}_{2}}\,\text{and }{{z}_{3}}\] represent the vertices A, B and C respectively of an isosceles triangle ABC of which \[\angle C\] is right angle, then correct statement is [RPET 1999]

A. \[{{z}_{1}}^{2}+{{z}_{2}}^{2}+{{z}_{3}}^{2}={{z}_{1}}{{z}_{2}}{{z}_{3}}\]
B. \[{{({{z}_{3}}-{{z}_{1}})}^{2}}={{z}_{3}}-{{z}_{2}}\]
C. \[{{({{z}_{1}}-{{z}_{2}})}^{2}}=({{z}_{1}}-{{z}_{3}})\,({{z}_{3}}-{{z}_{2}})\]
D. \[{{({{z}_{1}}-{{z}_{2}})}^{2}}=2({{z}_{1}}-{{z}_{3}})\,({{z}_{3}}-{{z}_{2}})\]
Answer» E.
4535.

 If the points \[{{P}_{1}}\]and \[{{P}_{2}}\] represent two complex numbers \[{{z}_{1}}\] and \[{{z}_{2}}\], then the point \[{{P}_{3}}\] represents the number

A. \[{{z}_{1}}+{{z}_{2}}\]
B. \[{{z}_{1}}-{{z}_{2}}\]
C. \[{{z}_{1}}\times {{z}_{2}}\]
D. \[{{z}_{1}}\div {{z}_{2}}\]
Answer» B. \[{{z}_{1}}-{{z}_{2}}\]
4536.

The equation \[z\overline{z}+(2-3i)z+(2+3i)\overline{z}+4=0\] represents a circle of radius    [Kurukshetra CEE 1996]

A. 2
B. 3
C. 4
D. 6
Answer» C. 4
4537.

The complex numbers \[{{z}_{1}},{{z}_{2}},{{z}_{3}}\] are the vertices of a triangle. Then the complex numbers \[z\] which make the triangle into a parallelogram is

A. \[{{z}_{1}}+{{z}_{2}}-{{z}_{3}}\]
B. \[{{z}_{1}}-{{z}_{2}}+{{z}_{3}}\]
C. \[{{z}_{2}}+{{z}_{3}}-{{z}_{1}}\]
D. All the above
Answer» E.
4538.

The points \[{{z}_{1}},\,{{z}_{2}},\,{{z}_{3}},\,{{z}_{4}}\] in the complex plane are the vertices of a parallelogram taken in order, if and only if [IIT 1981, 1983; UPSEAT 2004]

A. \[{{z}_{1}}+{{z}_{4}}={{z}_{2}}+{{z}_{3}}\]
B. \[{{z}_{1}}+{{z}_{3}}={{z}_{2}}+{{z}_{4}}\]
C. \[{{z}_{1}}+{{z}_{2}}={{z}_{3}}+{{z}_{4}}\]
D. None of these
Answer» C. \[{{z}_{1}}+{{z}_{2}}={{z}_{3}}+{{z}_{4}}\]
4539.

If \[{{z}_{1}},{{z}_{2}},{{z}_{3}},{{z}_{4}}\] are the affixes of four points in the Argand plane and \[z\] is the affix of a point such that \[|z-{{z}_{1}}|\,=\,|z-{{z}_{2}}|\,=\,|z-{{z}_{3}}|\,=|z-{{z}_{4}}|\], then \[{{z}_{1}},{{z}_{2}},{{z}_{3}},{{z}_{4}}\] are

A. Concyclic
B. Vertices of a parallelogram
C. Vertices of a rhombus
D. In a straight line
Answer» B. Vertices of a parallelogram
4540.

The vertices \[B\] and \[D\] of a parallelogram are \[1-2i\]and \[4+2i\],  If the diagonals are at right angles and \[AC=2BD\], the complex number representing \[A\] is

A. \[\frac{5}{2}\]
B. \[3i-\frac{3}{2}\]
C. \[3i-4\]
D. \[3i+4\]
Answer» C. \[3i-4\]
4541.

Let  \[a\] be a complex number such that \[|a|\,

A. \[|z-a|=a\]
B. \[\left| z-\frac{1}{1-a} \right|=|1-a|\]
C. \[\left| z-\frac{1}{1-a} \right|=\frac{1}{|1-a|}\]
D. \[|z-(1-a)|\,=|\,1-a|\]
Answer» D. \[|z-(1-a)|\,=|\,1-a|\]
4542.

The centre of a regular polygon of \[n\] sides is located at the point \[z=0\] and one of its vertex \[{{z}_{1}}\] is known. If \[{{z}_{2}}\] be the vertex adjacent to \[{{z}_{1}}\], then \[{{z}_{2}}\] is equal to

A. \[{{z}_{1}}\left( \cos \frac{2\pi }{n}\pm i\sin \frac{2\pi }{n} \right)\]
B. \[{{z}_{1}}\left( \cos \frac{\pi }{n}\pm i\sin \frac{\pi }{n} \right)\]
C. \[{{z}_{1}}\left( \cos \frac{\pi }{2n}\pm i\sin \frac{\pi }{2n} \right)\]
D. None of these
Answer» B. \[{{z}_{1}}\left( \cos \frac{\pi }{n}\pm i\sin \frac{\pi }{n} \right)\]
4543.

The vector \[z=3-4i\] is turned anticlockwise through an angle of \[{{180}^{o}}\] and stretched 2.5 times. The complex number corresponding to the newly obtained vector is

A. \[\frac{15}{2}-10i\]
B. \[\frac{-15}{2}+10i\]
C. \[\frac{-15}{2}-10i\]
D. None of these
Answer» C. \[\frac{-15}{2}-10i\]
4544.

\[POQ\] is a straight line through the origin \[O,\,\,P\] and \[Q\] represent the complex numbers \[a+ib\] and\[c+id\] respectively and \[OP=OQ\],  then

A. \[|a+ib|\,=\,|c+id|\]
B. \[a+c=b+d\]
C. \[arg(a+ib)=arg(c+id)\]
D. None of these
Answer» C. \[arg(a+ib)=arg(c+id)\]
4545.

If \[\omega \] is a complex number satisfying \[\left| \text{ }\omega +\frac{1}{\omega }\text{ } \right|=2\], then maximum distance of \[\omega \]from origin is

A. \[2+\sqrt{3}\]
B. \[1+\sqrt{2}\]
C. \[1+\sqrt{3}\]
D. None of these
Answer» C. \[1+\sqrt{3}\]
4546.

The number of triangles that can be formed by choosing the vertices from a set of 12 points, seven of which lie on the same straight line, is [Roorkee 1989; BIT 1989; MP PET 1995;Pb. CET 1997, 98; Roorkee 2000; DCE 2002; AMU 2005]

A. 185
B. 175
C. 115
D. 105
Answer» B. 175
4547.

The number of straight lines joining 8 points on a circle is [MP PET 1984]

A. 8
B. 16
C. 24
D. 28
Answer» E.
4548.

The number of diagonals in a polygon of \[m\] sides is          [BIT 1992; MP PET 1999; UPSEAT 1999; DCE 1999; Pb. CET 2001]

A. \[\frac{1}{2\ !}m(m-5)\]
B. \[\frac{1}{2\ !}m(m-1)\]
C. \[\frac{1}{2\ !}m(m-3)\]
D. \[\frac{1}{2\ !}m(m-2)\]
Answer» D. \[\frac{1}{2\ !}m(m-2)\]
4549.

How many triangles can be drawn by means of 9 non-collinear points

A. 84
B. 72
C. 144
D. 126
Answer» B. 72
4550.

If a polygon has 44 diagonals, then the number of its sides are                 [MP PET 1998; Pb. CET 1996, 2002]

A. 7
B. 11
C. 8
D. None of these
Answer» C. 8