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.

1351.

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

A. \[\frac{1}{{{\alpha }^{3}}+\alpha \beta },\frac{1}{{{\beta }^{3}}+\alpha \beta }\]
B. \[\frac{1}{{{\alpha }^{2}}+\alpha \beta },\frac{1}{{{\beta }^{2}}+\alpha \beta }\]
C. \[\frac{1}{{{\alpha }^{4}}+\alpha \beta },\frac{1}{{{\beta }^{4}}+\alpha \beta }\]
D. None of these
Answer» C. \[\frac{1}{{{\alpha }^{4}}+\alpha \beta },\frac{1}{{{\beta }^{4}}+\alpha \beta }\]
1352.

If z is a complex number such that \[z+|z|=8+12i,\] then the value of \[|{{z}^{2}}|\] is equal to

A. 228      
B. 144 
C. 121      
D. 169
Answer» E.
1353.

For the equation \[\left| {{x}^{2}} \right|+\left| x \right|-6=0,\] the roots are

A. One and only one real number
B. Real with sum one          
C. Real with sum zero
D. Real with product zero
Answer» D. Real with product zero
1354.

If \[{{z}_{1}},{{z}_{2}}\] and \[{{z}_{3}}\] are complex numbers such that \[\left| {{z}_{1}} \right|=\left| {{z}_{2}} \right|=\left| {{z}_{3}} \right|=\left| \frac{1}{{{z}_{1}}}+\frac{1}{{{z}_{2}}}+\frac{1}{{{z}_{3}}} \right|=1,\]  then \[\left| {{z}_{1}}+{{z}_{2}}+{{z}_{3}} \right|\]is

A. equal to 1       
B. less than 1
C. greater than 3   
D. equal to 3
Answer» B. less than 1
1355.

Let \[z={{\log }_{2}}(1+i),\] then \[(z+\bar{z})+i(z-\bar{z})=\]

A. \[\frac{\ln \,4+\pi }{\ln \,\,4}\]       
B. \[\frac{\pi -\ln \,4}{\ln \,\,2}\]
C. \[\frac{\ln \,4-\pi }{\ln \,\,4}\]
D. \[\frac{\pi +\ln \,\,4}{\ln \,\,2}\]
Answer» D. \[\frac{\pi +\ln \,\,4}{\ln \,\,2}\]
1356.

If the roots of the equation \[{{x}^{2}}-ax+b=0\] are real and differ by a quantity which is less than \[c(c>0),\] then b lies between

A. \[\frac{{{a}^{2}}-{{c}^{2}}}{4}\] and \[\frac{{{a}^{2}}}{4}\]
B. \[\frac{{{a}^{2}}+{{c}^{2}}}{4}\] and \[\frac{{{a}^{2}}}{4}\]
C. \[\frac{{{a}^{2}}-{{c}^{2}}}{2}\] and \[\frac{{{a}^{2}}}{4}\]
D. None of these
Answer» B. \[\frac{{{a}^{2}}+{{c}^{2}}}{4}\] and \[\frac{{{a}^{2}}}{4}\]
1357.

What is \[{{\left[ \frac{\sin \frac{\pi }{6}+i\left( 1-\cos \frac{\pi }{6} \right)}{\sin \frac{\pi }{6}-i\left( 1-\cos \frac{\pi }{6} \right)} \right]}^{3}}\] where \[i=\sqrt{-1},\] equal to?

A. 1                     
B. \[-1\]  
C. \[i\]     
D. \[-i\]
Answer» D. \[-i\]
1358.

The roots of the equation \[ab{{c}^{2}}{{x}^{2}}+3{{a}^{2}}cx+{{b}^{2}}cx-6{{a}^{2}}-ab+2{{b}^{2}}=0\] are

A. non real
B. rational if a, b, c are rational
C. irrational if a, b, c are rational
D. None of these
Answer» C. irrational if a, b, c are rational
1359.

The value of \[Arg\left[ i\,\,\ln \left( \frac{a-ib}{a+ib} \right) \right],\] where a and b are real numbers, is

A. \[0\] or \[\pi \] 
B. \[\frac{\pi }{2}\]
C. not defined     
D. None of these
Answer» B. \[\frac{\pi }{2}\]
1360.

If the roots of \[a{{x}^{2}}+bx+c=0\] are the reciprocals of those of \[\ell {{x}^{2}}+mx+n=0\] then \[a:b:c=\]

A. \[n:m:\ell \]        
B. \[\ell :m:n\]
C. \[m:n:\ell \]        
D. \[n:\ell :m\]
Answer» B. \[\ell :m:n\]
1361.

If \[z=1+i\tan \alpha \,\left( -\pi

A. \[\frac{1}{\cos \alpha }(\cos \alpha +i\sin \alpha )\]
B. \[\frac{1}{-\cos \alpha }[\cos \,(\pi +\alpha )+i\sin (\pi +\alpha )\]
C. \[\frac{1}{\cos \alpha }[\cos \,(2\pi +\alpha )+i\sin (2\pi +\alpha )]\]
D. None of these
Answer» C. \[\frac{1}{\cos \alpha }[\cos \,(2\pi +\alpha )+i\sin (2\pi +\alpha )]\]
1362.

If \[\alpha \] and \[\beta \] \[(\alpha

A. \[0<\alpha <\beta \]     
B. \[\alpha <0<\beta <\,|\alpha |\]
C. \[\alpha <\beta <0\]     
D. \[\alpha <0<\,|\alpha |\,<\beta \]
Answer» C. \[\alpha <\beta <0\]     
1363.

Suppose the quadratic equations \[{{x}^{2}}+px+q=0\] and \[{{x}^{2}}+rx+s=0\] are such that p, q, r, s are real and \[pr=2(q+s).\] Then

A. Both the equations always have real roots
B. At least one equation always has real roots
C. Both the equation always have non real roots
D. At least one equation always has real and equal roots
Answer» C. Both the equation always have non real roots
1364.

If \[{{z}_{1}},{{z}_{2}}\] are the roots of the quadratic equation \[a{{z}^{2}}+bz+c=0\] such that \[\operatorname{Im}({{z}_{1}},{{z}_{2}})\ne 0\] then

A. a, b, c are all real
B. at least one of a, b, c is real
C. at least one of a, b, c is imaginary
D. all of a, b, c are imaginary
Answer» D. all of a, b, c are imaginary
1365.

What is the real part of \[{{(\sin x+i\cos x)}^{3}}\]where\[i=\sqrt{-1}\] ?

A. \[-\cos \,3x\]        
B. \[-\sin \,3x\]
C. \[\sin \,3x\]          
D. \[\cos \,3x\]
Answer» C. \[\sin \,3x\]          
1366.

What is the argument of \[(1-\sin \theta )+i\cos \theta \]?

A. \[\frac{\pi }{2}-\frac{\theta }{2}\]            
B. \[\frac{\pi }{2}+\frac{\theta }{2}\]
C. \[\frac{\pi }{4}-\frac{\theta }{2}\]           
D. \[\frac{\pi }{4}+\frac{\theta }{2}\]
Answer» E.
1367.

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

A. \[pq{{x}^{2}}-pqx+{{p}^{2}}+{{q}^{2}}+4pq=0\]
B. \[{{p}^{2}}{{q}^{2}}{{x}^{2}}-{{p}^{2}}{{q}^{2}}x+{{p}^{3}}+{{q}^{3}}-4pq=0\]
C. \[{{p}^{3}}{{q}^{3}}{{x}^{2}}-{{p}^{3}}{{q}^{3}}x+{{p}^{4}}+{{q}^{4}}-4{{p}^{2}}{{q}^{2}}=0\]
D. \[(p+q){{x}^{2}}-(p+q)x+{{p}^{2}}+{{q}^{2}}+pq=0\]
Answer» C. \[{{p}^{3}}{{q}^{3}}{{x}^{2}}-{{p}^{3}}{{q}^{3}}x+{{p}^{4}}+{{q}^{4}}-4{{p}^{2}}{{q}^{2}}=0\]
1368.

Let \[\lambda \in \mathbf{R}\] If the origin and the non-real roots of \[2{{z}^{2}}+2z+\lambda =0\] form the three vertices of an equilateral triangle in the arg and plane. Then \[\lambda \] is

A. 1                     
B. \[\frac{2}{3}\]   
C. 2                     
D. \[-1\]
Answer» C. 2                     
1369.

If \[0

A. \[|\alpha =|\beta |\]      
B. \[|\alpha |\,>1\]
C. \[|\beta |\,<1\]         
D. None of these
Answer» D. None of these
1370.

If \[f({{x}_{1}})-f({{x}_{2}})=f\left( \frac{{{x}_{1}}-{{x}_{2}}}{1-{{x}_{1}}{{x}_{2}}} \right)\] for  then what is \[f(x)\] equal to?

A. \[\ln \left( \frac{1-x}{1+x} \right)\]
B. \[\ln \left( \frac{2+x}{1-x} \right)\]
C. \[{{\tan }^{-1}}\left( \frac{1-x}{1+x} \right)\]    
D. \[{{\tan }^{-1}}\left( \frac{1+x}{1-x} \right)\]
Answer» B. \[\ln \left( \frac{2+x}{1-x} \right)\]
1371.

If z in any complex number satisfying  then which of the following is correct?

A. \[\arg \,(z-1)=2argz\]
B. \[2\arg \,(z)=\frac{2}{3}arg({{z}^{2}}-z)\]
C. \[\arg (z-1)=\arg (z+1)\]
D. \[\arg z=2\arg (z+1)\]
Answer» B. \[2\arg \,(z)=\frac{2}{3}arg({{z}^{2}}-z)\]
1372.

Consider \[f(x)={{x}^{2}}-3x+a+\frac{1}{a},\]\[a\in R-\{0\},\]such that \[f(3)>0\] and \[f(2)\le 0.\] If \[\alpha \] and \[\beta \] are the roots of equation \[f(x)=0\] then the value of \[{{\alpha }^{2}}+{{\beta }^{2}}\] is equal to

A. greater than 11
B. less than 5
C. 5
D. depends upon a and a cannot be determined
Answer» D. depends upon a and a cannot be determined
1373.

If \[\omega \] is a complex cube root of unity and \[x={{\omega }^{2}}-\omega -2,\] then what is the value of \[{{x}^{2}}+4x+7\]?

A. \[-2\]    
B. \[-1\]  
C. \[0\]     
D. \[1\]
Answer» D. \[1\]
1374.

Let \[\alpha ,\beta \] be the roots of \[{{x}^{2}}+x+1=0.\] Then the equation whose roots are \[{{\alpha }^{229}}\] and \[{{\alpha }^{1004}}\] is

A. \[{{x}^{2}}-x-1=0\]
B. \[{{x}^{2}}-x+1=0\]
C. \[{{x}^{2}}+x-1=0\]  
D. \[{{x}^{2}}+x+1=0\]
Answer» E.
1375.

If the roots of the equations \[p{{x}^{2}}+2qx+r=0\]and \[q{{x}^{2}}-2\sqrt{pr}x+q=0\] be real, then

A. \[p=q\]             
B. \[{{q}^{2}}=pr\]
C. \[{{p}^{2}}=qr\]         
D. \[{{r}^{2}}=pr\]
Answer» C. \[{{p}^{2}}=qr\]         
1376.

The greatest and the least value of \[|{{z}_{1}}+{{z}_{2}}|\] if \[{{z}_{1}}=24+7i\] and \[|{{z}_{2}}|=6\] respectively are

A. \[25,\,\,19\]          
B. \[19,\,\,25\]
C. \[-19,\,\,-25\]        
D. \[-25,\,\,-19\]
Answer» B. \[19,\,\,25\]
1377.

The points \[{{z}_{1}},{{z}_{2}},{{z}_{3}},{{z}_{4}}\] in a complex plane are vertices of a parallelogram taken in order, then

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. \[{{z}_{1}}+{{z}_{2}}={{z}_{3}}+{{z}_{4}}\]
1378.

What is the value of \[{{\left( -\sqrt{-1} \right)}^{4n+3}}+{{\left( {{i}^{41}}+{{i}^{-257}} \right)}^{9}},\] where \[n\in N\]?

A. 0         
B. 1    
C. i                      
D. \[-i\]
Answer» D. \[-i\]
1379.

If \[\alpha ,\beta \] are roots of \[a{{x}^{2}}+bx+b=0,\] then \[\sqrt{\frac{\alpha }{\beta }}+\sqrt{\frac{\beta }{\alpha }}+\sqrt{\frac{b}{a}}\] is (\[{{b}^{2}}\ge 4ab,\] a and b are of same sign)

A. 0         
B. 1   
C. 2                     
D. \[2\sqrt{\frac{b}{a}}\]
Answer» E.
1380.

If both the roots of the equation \[{{x}^{2}}-2kx+{{k}^{2}}-4=0\] lie between \[-3\] and 5, then which one of the following is correct?

A. \[-2<k<2\]    
B. \[-5<k<3\]
C. \[-3<k<5\]    
D. \[-1<k<3\]
Answer» E.
1381.

The locus of a point in the Argand plane that moves satisfying the equation \[|z-1+i|-|z-2-i|=3:\]

A. is a circle with radius 3 and centre at \[z=\frac{3}{2}\]
B. is an ellipse with its foci at \[1-i\] and \[2+i\] and major axis \[=3\]
C. is a hyperbola with its foci at \[1-i\] and \[2+i\]and its transverse axis \[=3\]
D. None of the above
Answer» D. None of the above
1382.

The real roots of the equation \[{{x}^{2}}+5|x|+4=0\] are

A. \[\{-1,-4\}\]        
B. \[\{1,4\}\]
C. \[\{-4,4\}\]         
D. None of these
Answer» E.
1383.

If x be real and \[b

A. \[(b,c)\] 
B. \[[b,c]\]
C. \[(-\infty ,b]\cup [c,\infty )\]
D. \[(-\infty ,b)\cup (c,\infty )\]
Answer» D. \[(-\infty ,b)\cup (c,\infty )\]
1384.

\[A+iB\] form of \[\frac{(\cos x+i\sin x)(\cos y+i\sin y)}{(\cot u+i)(1+i\tan \,\,v)}\]is equal to:

A. \[\sin u\,\,\cos v\,\,[\cos (x+y-u-v)+\]\[i\sin (x+y-u-v)]\]
B. \[\sin \,u\,\cos \,v[\cos \,(x+y+u+v)+\]\[i\sin (x+y+u+v)]\]
C. \[\sin \,\,u\,\,\,\cos \,\,v\,\,[\cos \,(x+y+u+v)-\]\[i\sin (x+y-u+v)]\]
D. None of these
Answer» B. \[\sin \,u\,\cos \,v[\cos \,(x+y+u+v)+\]\[i\sin (x+y+u+v)]\]
1385.

If \[{{z}^{2}}+z+1=0,\] where z is complex number, then the value of \[{{\left( z+\frac{1}{z} \right)}^{2}}+{{\left( {{z}^{2}}+\frac{1}{{{z}^{2}}} \right)}^{2}}+{{\left( {{z}^{3}}+\frac{1}{{{z}^{3}}} \right)}^{2}}\] \[+....+{{\left( {{z}^{6}}+\frac{1}{{{z}^{6}}} \right)}^{2}}\]is

A. 18        
B. 54   
C. 6                     
D. 12
Answer» E.
1386.

If \[2x=3+5i,\] then what is the value of \[2{{x}^{3}}+2{{x}^{2}}-7x+72?\]

A. 4                     
B. \[-4\]  
C. 8                     
D. \[-8\]
Answer» B. \[-4\]  
1387.

\[\sum\limits_{k=33}^{65}{\left( \sin \frac{2k\pi }{8}-i\cos \frac{2k\pi }{8} \right)}\]

A. \[1+i\]              
B. \[1-i\]
C. \[1+\frac{i}{\sqrt{2}}\] 
D. \[\frac{1-i}{\sqrt{2}}\]
Answer» E.
1388.

If \[\operatorname{Re}\left( \frac{z-1}{z+1} \right)=0,\] where \[2=x+iy\] is a complex number, then which one of the following is correct?

A. \[z=1+i\]        
B. \[\left| z \right|=2\]
C. \[z=1-i\]
D. \[\left| z \right|=1\]
Answer» E.
1389.

For what value of \[\lambda \] the sum of the squares of the roots of \[{{x}^{2}}+(2+\lambda )x-\frac{1}{2}(1+\lambda )=0\] is minimum?

A. \[3/2\]  
B. 1   
C. \[1/2\]  
D. \[11/4\]
Answer» D. \[11/4\]
1390.

If n is a positive integer grater than unity and z is a complex satisfying the equation \[{{z}^{n}}={{(z+1)}^{n}},\]then

A. \[\operatorname{Re}(z)<2\]      
B. \[\operatorname{Re}(z)>0\]
C. \[\operatorname{Re}(z)=0\]        
D. z lies on \[x=-\frac{1}{2}\]
Answer» E.
1391.

Let Z and W be two complex numbers such that \[\left| Z \right|\le 1,\] \[\left| W \right|\le 1\] and \[\left| Z+i\,W \right|=\left| Z-i\overline{W} \right|=2.\] Then Z equals          

A. 1 or i     
B. i or \[-i\]
C. 1 or \[-i\]           
D. i or \[-1\]
Answer» D. i or \[-1\]
1392.

The set of all real numbers x for which \[{{x}^{2}}-[x+2]+x>0,\] is

A. \[\left( -\infty ,-2 \right)\cup \left( 2,\infty  \right)\]
B. \[\left( -\infty ,-\sqrt{2} \right)\cup \left( \sqrt{2},\infty  \right)\]
C. \[\left( -\infty ,-1 \right)\cup \left( 1,\infty  \right)\]
D. \[\left( \sqrt{2},\infty  \right)\]
Answer» C. \[\left( -\infty ,-1 \right)\cup \left( 1,\infty  \right)\]
1393.

Let \[a>0,\text{ }b>0\] and \[c>0\]. Then both the roots of the equation \[a{{x}^{2}}+bx+c=0\]                   

A. are real and negative
B. have negative real parts
C. are rational numbers
D. None of these
Answer» C. are rational numbers
1394.

The value of \[{{(1+2\omega +{{\omega }^{2}})}^{3n}}-{{(1+\omega +2{{\omega }^{2}})}^{3n}}\] is:

A.  0        
B. 1     
C. \[\omega \]        
D. \[{{\omega }^{2}}\]
Answer» B. 1     
1395.

Number of solutions of the equation, \[{{z}^{3}}+\frac{3{{\left| z \right|}^{2}}}{z}=0,\] where z is a complex number and \[|z|=\sqrt{3}\] is

A. 2                     
B. 3    
C. 6                     
D. 4
Answer» E.
1396.

If \[z=\frac{-2\left( 1+2i \right)}{3+i}\] where \[i=\sqrt{-1},\] then argument \[\theta \,(-\pi

A. \[\frac{3\pi }{4}\]                      
B. \[\frac{\pi }{4}\]
C. \[\frac{5\pi }{6}\]                      
D. \[-\frac{3\pi }{4}\]
Answer» C. \[\frac{5\pi }{6}\]                      
1397.

If \[\alpha ,\beta ,\gamma \] and a, b, c are complex numbers such that \[\frac{\alpha }{a}+\frac{\beta }{b}+\frac{\gamma }{c}=1+i\] and \[\frac{a}{\alpha }+\frac{b}{\beta }+\frac{c}{\gamma }=0,\] then the value of \[\frac{{{\alpha }^{2}}}{{{a}^{2}}}+\frac{{{\beta }^{2}}}{{{b}^{2}}}+\frac{{{\gamma }^{2}}}{{{c}^{2}}}\] is equal to

A. \[0\]                 
B. \[-1\]   
C. \[2i\]   
D. \[-2i\]
Answer» D. \[-2i\]
1398.

The principle value of the \[\arg \,(z)\] and \[|z|\] of the complex number \[z=1+\cos \left( \frac{11\pi }{9} \right)+i\sin \left( \frac{11\pi }{9} \right)\] are respectively.

A. \[\frac{11\pi }{8},\,2\cos \left( \frac{\pi }{18} \right)\]
B. \[-\frac{7\pi }{18},-2\cos \left( \frac{11\pi }{18} \right)\]
C. \[\frac{2\pi }{9},2\cos \left( \frac{7\pi }{18} \right)\]
D. \[-\frac{\pi }{9},-2\cos \left( \frac{\pi }{18} \right)\]
Answer» C. \[\frac{2\pi }{9},2\cos \left( \frac{7\pi }{18} \right)\]
1399.

If \[\omega \] is imaginary cube root of unity, then \[\sin \left\{ ({{\omega }^{13}}+{{\omega }^{2}})\pi +\frac{\pi }{4} \right\}\] is equal to

A. \[-\frac{\sqrt{3}}{2}\]    
B. \[-\frac{1}{\sqrt{2}}\]
C. \[\frac{1}{\sqrt{2}}\]                 
D. \[\frac{\sqrt{3}}{2}\]
Answer» C. \[\frac{1}{\sqrt{2}}\]                 
1400.

Let \[{{x}_{1}}\] and \[{{y}_{1}}\] be real numbers. If \[{{z}_{1}}\] and \[{{z}_{2}}\] are complex numbers such that \[|{{z}_{1}}|=|{{z}_{2}}|=4,\] then \[|{{x}_{1}}{{z}_{1}}-{{y}_{1}}{{z}_{2}}{{|}^{2}}+|{{y}_{1}}{{z}_{1}}+{{x}_{1}}{{z}_{2}}{{|}^{2}}=\]

A. \[32({{x}_{1}}^{2}+{{y}_{1}}^{2})\]                      
B. \[16({{x}_{1}}^{2}+{{y}_{1}}^{2})\]
C. \[4({{x}_{1}}^{2}+{{y}_{1}}^{2})\]            
D. \[32({{x}_{1}}^{2}+{{y}_{1}}^{2})|{{z}_{1}}+{{z}_{2}}{{|}^{2}}\]
Answer» B. \[16({{x}_{1}}^{2}+{{y}_{1}}^{2})\]