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.

8501.

The roots of the quadratic equation \[2{{x}^{2}}+3x+1=0\], are [IIT 1983]

A. Irrational
B. Rational
C. Imaginary
D. None of these
Answer» C. Imaginary
8502.

If \[a+b+c=0\], then the roots of the equation \[4a{{x}^{2}}+3bx+2c=0\] are

A. Equal
B. Imaginary
C. Real
D. None of these
Answer» D. None of these
8503.

If the roots of the equation \[a{{x}^{2}}+x+b=0\] be real, then the roots of the equation \[{{x}^{2}}-4\sqrt{ab}x+1=0\] will be

A. Rational
B. Irrational
C. Real
D. Imaginary
Answer» E.
8504.

The roots of \[|x-2{{|}^{2}}+|x-2|-6=0\]are [UPSEAT 2003]

A. 0, 4
B. -1, 3
C. 4, 2
D. 5, 1
Answer» B. -1, 3
8505.

A real root of the equation \[{{\log }_{4}}\{{{\log }_{2}}(\sqrt{x+8}-\sqrt{x})\}=0\] is [AMU 1999]

A. 1
B. 2
C. 3
D. 4
Answer» B. 2
8506.

The equation\[{{e}^{x}}-x-1=0\] has [Kurukshetra CEE 1998]

A. Only one real root \[x=0\]
B. At least two real roots
C. Exactly two real roots
D. Infinitely many real roots
Answer» B. At least two real roots
8507.

The roots of the equation \[i{{x}^{2}}-4x-4i=0\] are

A. \[-2i\]
B. \[2i\]
C. \[-2i,-2i\]
D. \[2i,2i\]
Answer» D. \[2i,2i\]
8508.

The value of \[2+\frac{1}{2+\frac{1}{2+...........\infty }}\] is

A. \[1-\sqrt{2}\]
B. \[1+\sqrt{2}\]
C. \[1\pm \sqrt{2}\]
D. None of these
Answer» C. \[1\pm \sqrt{2}\]
8509.

The number of real roots of the equation \[{{e}^{\sin x}}-{{e}^{-\sin x}}-4\] \[=0\] are [IIT 1982; Pb. CET 2000]

A. 1
B. 2
C. Infinite
D. None
Answer» E.
8510.

If m and n are the roots of the equation \[(x+p)(x+q)-k=0,\] then the roots of the equation \[(x-m)(x-n)+k=0\] are

A. p and q
B. \[\frac{1}{p}\] and \[\frac{1}{q}\]
C. \[-p\]and \[-q\]
D. \[p+q\] and \[p-q\]
Answer» D. \[p+q\] and \[p-q\]
8511.

The value of the sum \[\sum\limits_{n=1}^{13}{\left( {{i}^{n}}+{{i}^{n+1}} \right)};\] where \[i=\sqrt{-1}\] is:

A. \[i\]
B. \[-i\]
C. \[0\]
D. \[i-1\]
Answer» E.
8512.

If z, \[\omega z\] ane \[\bar{\omega }z\] are the vertices of a triangle, then the area of the triangle will be (where \[\omega \] is cube root of unity):

A. \[\frac{3|z{{|}^{2}}}{2}\]
B. \[\frac{3\sqrt{3}|z{{|}^{2}}}{2}\]
C. \[\frac{\sqrt{3}|z{{|}^{2}}}{2}\]
D. None of these
Answer» C. \[\frac{\sqrt{3}|z{{|}^{2}}}{2}\]
8513.

The equation whose roots are the \[{{n}^{th}}\] power of the roots of the equation \[{{x}^{2}}-2x\,cos\theta +1=0\] is given by

A. \[{{x}^{2}}+2x\,\cos \,\,n\theta +1=0\]
B. \[{{x}^{2}}-2x\,\cos \,\,n\theta +1=0\]
C. \[{{x}^{2}}-2x\,sin\,\,n\theta +1=0\]
D. \[{{x}^{2}}+2x\,sin\,\,n\theta +1=0\]
Answer» C. \[{{x}^{2}}-2x\,sin\,\,n\theta +1=0\]
8514.

If \[\frac{1}{2-\sqrt{-2}}\] is one of the roots of \[a{{x}^{2}}+bx+c=0,\]where a, b, c are real, then what are the values of a, b, c respectively?

A. \[6,-4,1\]
B. \[4,6,-1\]
C. \[3,-2,1\]
D. \[6,4,1\]
Answer» B. \[4,6,-1\]
8515.

If \[f(z)=\frac{7-z}{1-{{z}^{2}}},\] where \[z=1+2i,\] then \[|f(z)|\] is equal to:

A. \[\frac{|z|}{2}\]
B. \[|z|\]
C. \[2|z|\]
D. None of these
Answer» B. \[|z|\]
8516.

If \[\lambda \ne \mu \] and \[{{\lambda }^{2}}=5\lambda -3,\]\[{{\mu }^{2}}=5\mu -3,\] then the equation whose roots are \[\frac{\lambda }{\mu }\] and \[\frac{\mu }{\lambda }\] is

A. \[{{x}^{2}}-5x+3=0\]
B. \[3{{x}^{2}}+19x+3=0\]
C. \[3{{x}^{2}}-19x+3=0\]
D. \[{{x}^{2}}+5x-3=0\]
Answer» D. \[{{x}^{2}}+5x-3=0\]
8517.

If \[1,\omega ,{{\omega }^{2}}\] are the three cube roots of unity, then what is \[\frac{(a{{\omega }^{6}}+b{{\omega }^{4}}+c{{\omega }^{2}})}{(b+c{{\omega }^{10}}+a{{\omega }^{8}})}\] equal to?

A. \[\frac{a}{b}\]
B. b
C. \[\omega \]
D. \[{{\omega }^{2}}\]
Answer» D. \[{{\omega }^{2}}\]
8518.

If z and \[\omega \] are two non-zero complex numbers such that \[\left| z\omega \right|=1\] and \[Arg(z)-Arg(\omega )=\frac{\pi }{2},\]then \[\bar{z}\omega \] is equal to

A. \[-i\]
B. \[1\]
C. \[-1\]
D. \[i\]
Answer» D. \[i\]
8519.

If \[{{m}_{1}},{{m}_{2}},{{m}_{3}}\] and \[{{m}_{4}}\] respectively denote the moduli of the complex numbers \[1+4i,\,\,3+i,\,\,1-i\] and \[2-3i,\] then the correct one, among the following is

A. \[{{m}_{1}}<{{m}_{2}}<{{m}_{3}}<{{m}_{4}}\]
B. \[{{m}_{4}}<{{m}_{3}}<{{m}_{2}}<{{m}_{1}}\]
C. \[{{m}_{3}}<{{m}_{2}}<{{m}_{4}}<{{m}_{1}}\]
D. \[{{m}_{3}}<{{m}_{1}}<{{m}_{2}}<{{m}_{4}}\]
Answer» D. \[{{m}_{3}}<{{m}_{1}}<{{m}_{2}}<{{m}_{4}}\]
8520.

The value of a for which the sum of the squares of the roots of the equation \[2{{x}^{2}}-2(a-2)x-(a+1)=0\] is least, is

A. 1
B. \[3/2\]
C. 2
D. None
Answer» C. 2
8521.

The values of k for which the equations \[{{x}^{2}}-kx-21=0\] and \[{{x}^{2}}-3kx+35=0\] will have a common roots are:

A. \[k=\pm 4\]
B. \[k=\pm 1\]
C. \[k=\pm 3\]
D. \[k=0\]
Answer» B. \[k=\pm 1\]
8522.

Roots of the equation \[{{x}^{2}}+bx-c=0(b,c>0)\]are

A. Both positive
B. Both negative
C. Of opposite sign
D. None of these
Answer» D. None of these
8523.

Sum of roots is \[-1\] and sum of their reciprocals is \[\frac{1}{6}\], then equation is [Karnataka CET 1998]

A. \[{{x}^{2}}+x-6=0\]
B. \[{{x}^{2}}-x+6=0\]
C. \[6{{x}^{2}}+x+1=0\]
D. \[{{x}^{2}}-6x+1=0\]
Answer» B. \[{{x}^{2}}-x+6=0\]
8524.

The equation formed by decreasing each root of \[a{{x}^{2}}+bx+c=0\] by 1 is \[2{{x}^{2}}+8x+2=0,\] then [EAMCET 2000]

A. a = - b
B. b = - c
C. c = - a
D. b = a + c
Answer» C. c = - a
8525.

If \[\alpha ,\beta \] are the roots of the equation \[l{{x}^{2}}+mx+n=0\], then the equation whose roots are \[{{\alpha }^{3}}\beta \] and \[\alpha {{\beta }^{3}}\] is [MP PET 1997]

A. \[{{l}^{4}}{{x}^{2}}-nl({{m}^{2}}-2nl)x+{{n}^{4}}=0\]
B. \[{{l}^{4}}{{x}^{2}}+nl({{m}^{2}}-2nl)x+{{n}^{4}}=0\]
C. \[{{l}^{4}}{{x}^{2}}+nl({{m}^{2}}-2nl)x-{{n}^{4}}=0\]
D. \[{{l}^{4}}{{x}^{2}}-nl({{m}^{2}}+2nl)x+{{n}^{4}}=0\]
Answer» B. \[{{l}^{4}}{{x}^{2}}+nl({{m}^{2}}-2nl)x+{{n}^{4}}=0\]
8526.

If \[a{{(p+q)}^{2}}+2bpq+c=0\] and \[a{{(p+r)}^{2}}+2bpr+c=0\], then \[qr\]=

A. \[{{p}^{2}}+\frac{c}{a}\]
B. \[{{p}^{2}}+\frac{a}{c}\]
C. \[{{p}^{2}}+\frac{a}{b}\]
D. \[{{p}^{2}}+\frac{b}{a}\]
Answer» B. \[{{p}^{2}}+\frac{a}{c}\]
8527.

A two digit number is four times the sum and three times the product of its digits. The number is [MP PET 1994]

A. 42
B. 24
C. 12
D. 21
Answer» C. 12
8528.

If \[\alpha \] and \[\beta \] are roots of \[a{{x}^{2}}+2bx+c=0\], then \[\sqrt{\frac{\alpha }{\beta }}+\sqrt{\frac{\beta }{\alpha }}\]is equal to [BIT Ranchi 1990]

A. \[\frac{2b}{ac}\]
B. \[\frac{2b}{\sqrt{ac}}\]
C. \[-\frac{2b}{\sqrt{ac}}\]
D. \[\frac{-b}{\sqrt{2}}\]
Answer» D. \[\frac{-b}{\sqrt{2}}\]
8529.

If \[\alpha \] and \[\beta \] are the roots of the equation \[4{{x}^{2}}+3x+7=0\], then \[\frac{1}{\alpha }+\frac{1}{\beta }\]= [MNR 1981; RPET 1990]

A. \[-\frac{3}{7}\]
B. \[\frac{3}{7}\]
C. \[-\frac{3}{5}\]
D. \[\frac{3}{5}\]
Answer» B. \[\frac{3}{7}\]
8530.

If \[\alpha ,\beta \] be the roots of the equation \[{{x}^{2}}-2x+3=0\], then the equation whose roots are \[\frac{1}{{{\alpha }^{2}}}\]and \[\frac{1}{{{\beta }^{2}}}\] is

A. \[{{x}^{2}}+2x+1=0\]
B. \[9{{x}^{2}}+2x+1=0\]
C. \[9{{x}^{2}}-2x+1=0\]
D. \[9{{x}^{2}}+2x-1=0\]
Answer» C. \[9{{x}^{2}}-2x+1=0\]
8531.

If \[\alpha ,\beta \] are the roots of the equation \[6{{x}^{2}}-5x+1=0\]. Then the value of \[{{\tan }^{-1}}\alpha +{{\tan }^{-1}}\beta \]is [MP PET 2004]

A. \[\pi /4\]
B. 1
C. 0
D. \[\pi /2\]
Answer» B. 1
8532.

If \[\alpha \] and \[\beta \] are the roots of the equation \[{{x}^{2}}+6x+\lambda =0\] and \[3\alpha +2\beta =-20\], then \[\lambda =\]

A. -8
B. -16
C. 16
D. 8
Answer» C. 16
8533.

Let \[z=1-t+i \sqrt{{{t}^{2}}+t+2}\], where t is a real parameter. The locus of z in the argand plane is

A. a hyperbola
B. an ellipse
C. a straight line
D. none of these
Answer» B. an ellipse
8534.

If a, b, c, d\[\in \]R, then the equation \[({{x}^{2}}+ax-3b)\]\[({{x}^{2}}-cx+b)\]\[({{x}^{2}}-dx+2b)\]=0 has

A. 6 real roots
B. at least 2 real roots
C. 4 real toots
D. 3 real roots
Answer» C. 4 real toots
8535.

If \[{{\left( \frac{1+i\sqrt{3}}{1-i\sqrt{3}} \right)}^{n}}\] is an integer, then n is [UPSEAT 2002]

A. 1
B. 2
C. 3
D. 4
Answer» D. 4
8536.

If \[z=x+iy,\,{{z}^{1/3}}=a-ib\] and \[\frac{x}{a}-\frac{y}{b}=k\,({{a}^{2}}-{{b}^{2}})\] then value of k equals [DCE 2005]

A. 2
B. 4
C. 6
D. 1
Answer» C. 6
8537.

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
8538.

The value of \[\frac{(\cos \alpha +i\,\sin \alpha )\,(\cos \beta +i\,\sin \beta )}{(\cos \gamma +i\,\sin \gamma )\,(\cos \,\delta +i\,\sin \delta )}\] is [RPET 2001]

A. \[\cos (\alpha +\beta -\gamma -\delta )-i\,\sin (\alpha +\beta -\gamma -\delta )\]
B. \[\cos (\alpha +\beta -\gamma -\delta )+i\,\sin (\alpha +\beta -\gamma -\delta )\]
C. \[\sin (\alpha +\beta -\gamma -\delta )-i\,\cos (\alpha +\beta -\gamma -\delta )\]
D. \[\sin (\alpha +\beta -\gamma -\delta )+i\,\cos (\alpha +\beta -\gamma -\delta )\]
Answer» C. \[\sin (\alpha +\beta -\gamma -\delta )-i\,\cos (\alpha +\beta -\gamma -\delta )\]
8539.

\[\frac{{{(\cos \theta +i\sin \theta )}^{4}}}{{{(\sin \theta +i\cos \theta )}^{5}}}\] is equal to [MNR 1985; UPSEAT 2000]

A. \[\cos \theta -i\sin \theta \]
B. \[\cos 9\theta -i\sin 9\theta \]
C. \[\sin \theta -i\cos \theta \]
D. \[\sin 9\theta -i\cos 9\theta \]
Answer» E.
8540.

The real part of \[{{(1-\cos \theta +2i\sin \theta )}^{-1}}\]is [IIT 1978, 86]

A. \[\frac{1}{3+5\cos \theta }\]
B. \[\frac{1}{5-3\cos \theta }\]
C. \[\frac{1}{3-5\cos \theta }\]
D. \[\frac{1}{5+3\cos \theta }\]
Answer» E.
8541.

The complex numbers \[z=x+iy\] which satisfy the equation \[\left| \frac{z-5i}{z+5i} \right|=1\] lie on [IIT 1982]

A. Real axis
B. The line \[y=5\]
C. A circle passing through the origin
D. None of these
Answer» B. The line \[y=5\]
8542.

The cube roots of unity when represented on the Argand plane form the vertices of an [IIT 1988; Pb. CET 2004]

A. Equilateral triangle
B. Isosceles triangle
C. Right angled triangle
D. None of these
Answer» B. Isosceles triangle
8543.

If \[z=\frac{-2}{1+\sqrt{3}\,i}\] then the value of \[arg\,(z)\] is [ Orissa JEE 2002]

A. \[\pi \]
B. \[\pi /3\]
C. \[2\pi /3\]
D. \[\pi /4\]
Answer» D. \[\pi /4\]
8544.

Let \[{{\omega }_{n}}=\cos \left( \frac{2\pi }{n} \right)+i\,\sin \left( \frac{2\pi }{n} \right)\,,\,{{i}^{2}}=-1\], then \[(x+y{{\omega }_{3}}+z{{\omega }_{3}}^{2})\] \[(x+y{{\omega }_{3}}^{2}+z{{\omega }_{3}})\] is equal to [AMU 2001]

A. 0
B. \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}\]
C. \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}-yz-zx-xy\]\[\]
D. \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}+yz+zx+xy\]
Answer» D. \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}+yz+zx+xy\]
8545.

\[ABCD\] is a rhombus. Its diagonals \[AC\] and \[BD\] intersect at the point \[M\] and satisfy \[BD=2AC\]. If the points \[D\] and \[M\] represents the complex numbers \[1+i\] and \[2-i\] respectively, then \[A\] represents the complex number

A. \[3-\frac{1}{2}i\]or \[1-\frac{3}{2}i\]
B. \[\frac{3}{2}-i\]or \[\frac{1}{2}-3i\]
C. \[\frac{1}{2}-i\]or \[1-\frac{1}{2}i\]
D. None of these
Answer» B. \[\frac{3}{2}-i\]or \[\frac{1}{2}-3i\]
8546.

The line \[ax+by+c=0\] is a normal to the circle \[{{x}^{2}}+{{y}^{2}}={{r}^{2}}\]. The portion of the line \[ax+by+c=0\] intercepted by this circle is of length

A. r
B. \[{{r}^{2}}\]
C. 2r
D. \[\sqrt{r}\]
Answer» D. \[\sqrt{r}\]
8547.

A point inside the circle \[{{x}^{2}}+{{y}^{2}}+3x-3y+2=0\]is [MP PET 1988]

A. (- 1, 3)
B. (- 2, 1)
C. (2, 1)
D. (- 3, 2)
Answer» C. (2, 1)
8548.

The line \[lx+my+n=0\]is normal to the circle \[{{x}^{2}}+{{y}^{2}}+2gx+2fy+c=0\], if [MP PET 1995]

A. \[lg+mf-n=0\]
B. \[lg+mf+n=0\]
C. \[lg=mf-n=0\]
D. \[lg-mf+n=0\]
Answer» B. \[lg+mf+n=0\]
8549.

The two circles which passes through \[(0,a)\]and \[(0,-a)\]and touch the line \[y=mx+c\] will intersect each other at right angle, if

A. \[{{a}^{2}}={{c}^{2}}(2m+1)\]
B. \[{{a}^{2}}={{c}^{2}}(2+{{m}^{2}})\]
C. \[{{c}^{2}}={{a}^{2}}(2+{{m}^{2}})\]
D. \[{{c}^{2}}={{a}^{2}}(2m+1)\]
Answer» D. \[{{c}^{2}}={{a}^{2}}(2m+1)\]
8550.

Which of the following lines is a tangent to the circle \[{{x}^{2}}+{{y}^{2}}=25\]for all values of m

A. \[y=mx+25\sqrt{1+{{m}^{2}}}\]
B. \[y=mx+5\sqrt{1+{{m}^{2}}}\]
C. \[y=mx+25\sqrt{1-{{m}^{2}}}\]
D. \[y=mx+5\sqrt{1-{{m}^{2}}}\]
Answer» C. \[y=mx+25\sqrt{1-{{m}^{2}}}\]