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.

1151.

The differential equations of all conies whose axes coincide with the co-ordinate axis

A. \[xy\frac{{{d}^{2}}y}{d{{x}^{2}}}+x{{\left( \frac{dy}{dx} \right)}^{2}}+y\frac{dy}{dx}=0\]
B. \[xy\frac{{{d}^{2}}y}{d{{x}^{2}}}+x{{\left( \frac{dy}{dx} \right)}^{2}}+x\frac{dy}{dx}=0\]
C. \[xy\frac{{{d}^{2}}y}{d{{x}^{2}}}+x{{\left( \frac{dy}{dx} \right)}^{2}}-y\frac{dy}{dx}=0\]
D. \[xy\frac{{{d}^{2}}y}{d{{x}^{2}}}-x{{\left( \frac{dy}{dx} \right)}^{2}}+y\frac{dy}{dx}=0\]
Answer» D. \[xy\frac{{{d}^{2}}y}{d{{x}^{2}}}-x{{\left( \frac{dy}{dx} \right)}^{2}}+y\frac{dy}{dx}=0\]
1152.

A differential equation associated with the primitive \[y=a+b{{e}^{5x}}+c{{e}^{-~7x}}\] is

A. \[{{y}_{3}}+2{{y}_{2}}-{{y}_{1}}=0\]
B. \[{{y}_{3}}+2{{y}_{2}}-35{{y}_{1}}=0\]
C. \[4{{y}_{3}}+5{{y}_{2}}-20{{y}_{1}}=0\]
D. None of these
Answer» C. \[4{{y}_{3}}+5{{y}_{2}}-20{{y}_{1}}=0\]
1153.

The particular solution of the differential equation \[{{\sin }^{-1}}\left( \frac{{{d}^{2}}y}{d{{x}^{2}}}-1 \right)=x\], where\[y=\frac{dy}{dx}=0\] when\[x=0\], is

A. \[y={{x}^{2}}+x-\sin x\]
B. \[y=\frac{{{x}^{2}}}{2}+x-\sin x\]
C. \[y=\frac{{{x}^{2}}}{2}+\frac{x}{2}-\sin x\]
D. \[2y={{x}^{2}}+x-\sin x\]
Answer» C. \[y=\frac{{{x}^{2}}}{2}+\frac{x}{2}-\sin x\]
1154.

The degree of differential equation satisfying the relation\[\sqrt{1+{{x}^{2}}}+\sqrt{1+{{y}^{2}}}=\lambda (x\sqrt{1+{{y}^{2}}}-y\sqrt{1+{{x}^{2}}})\] is

A. 1
B. 2
C. 3
D. 4
Answer» B. 2
1155.

The differential equation\[(1+{{y}^{2}})xdx-(1+{{x}^{2}})ydy=0\] Represents a family of:

A. Ellipses of constant eccentricity
B. Ellipses of variable eccentricity-
C. Hyperbolas of constant eccentricity
D. Hyperbolas of variable eccentricity
Answer» E.
1156.

Which of the following does not represent the orthogonal trajectory of the system of curves \[{{\left( \frac{dy}{dx} \right)}^{2}}=\frac{a}{x}\]

A. \[9a{{(y+c)}^{2}}=4{{x}^{3}}\]
B. \[y+c=\frac{-2}{3\sqrt{a}}{{x}^{3/2}}\]
C. \[y+c=\frac{2}{3\sqrt{a}}{{x}^{3/2}}\]
D. All are orthogonal trajectories
Answer» E.
1157.

The general solution of \[(x+1)\frac{dy}{dx}+1=2{{e}^{-y}}\] is

A. \[{{e}^{y}}(x+1)=x+C\]
B. \[{{e}^{-y}}=2x+C\]
C. \[{{e}^{y}}(x+1)=2x+C\]
D. \[{{e}^{y}}(x+1)=C\]
Answer» D. \[{{e}^{y}}(x+1)=C\]
1158.

The differential equation of the family of circles with fixed radius 5 units and centre on the line \[y=2\] is

A. \[(y-2)y{{'}^{2}}=25-{{(y-2)}^{2}}\]
B. \[{{(y-2)}^{2}}y{{'}^{2}}=25-{{(y-2)}^{2}}\]
C. \[{{(x-2)}^{2}}y{{'}^{2}}=25-{{(y-2)}^{2}}\]
D. \[(x-2)y{{'}^{2}}=25-{{(y-2)}^{2}}\]
Answer» C. \[{{(x-2)}^{2}}y{{'}^{2}}=25-{{(y-2)}^{2}}\]
1159.

What is the solution of \[\frac{dy}{dx}+2y=1\] satisfying\[y(0)=0\]?

A. \[y=\frac{1-{{e}^{-2x}}}{2}\]
B. \[y=\frac{1+{{e}^{-2x}}}{2}\]
C. \[y=1+{{e}^{x}}\]
D. \[y=\frac{1+{{e}^{x}}}{2}\]
Answer» B. \[y=\frac{1+{{e}^{-2x}}}{2}\]
1160.

Which one of the following differential equations represents the family of straight lines which are at unit distance from the origin?

A. \[{{\left( y-x\frac{dy}{dx} \right)}^{2}}=1-{{\left( \frac{dy}{dx} \right)}^{2}}\]
B. \[{{\left( y+x\frac{dy}{dx} \right)}^{2}}=1+{{\left( \frac{dy}{dx} \right)}^{2}}\]
C. \[{{\left( y-x\frac{dy}{dx} \right)}^{2}}=1+{{\left( \frac{dy}{dx} \right)}^{2}}\]
D. \[{{\left( y+x\frac{dy}{dx} \right)}^{2}}=1-{{\left( \frac{dy}{dx} \right)}^{2}}\]
Answer» D. \[{{\left( y+x\frac{dy}{dx} \right)}^{2}}=1-{{\left( \frac{dy}{dx} \right)}^{2}}\]
1161.

The solution of \[\frac{dy}{dx}=\sqrt{1-{{x}^{2}}-{{y}^{2}}+{{x}^{2}}{{y}^{2}}}\] is

A. \[si{{n}^{-1}}y=si{{n}^{-1}}x+c\]
B. \[2si{{n}^{-1}}y=\sqrt{1-{{x}^{2}}}+si{{n}^{-1}}x+c\]
C. \[2si{{n}^{-1}}y=x\sqrt{1-{{x}^{2}}}+si{{n}^{-1}}x+c\]
D. \[2si{{n}^{-1}}y=x\sqrt{1-{{x}^{2}}}+{{\cos }^{-1}}x+c\]
Answer» E.
1162.

The general solution of the differential equation \[\frac{dy}{dx}-\frac{\tan \,\,y}{1+x}=(1+x){{e}^{x}}\sec \,\,y\] is

A. \[\sin (1+x)=y({{e}^{x}}+c)\]
B. \[y\sin (1+x)=c{{e}^{x}}\]
C. \[(1+x)sin\,\,y={{e}^{x}}+c\]
D. \[\sin \,\,y=(1+x)({{e}^{x}}+c)\]
Answer» E.
1163.

The curve satisfying the equation \[\frac{dy}{dx}=\frac{y(x+{{y}^{3}})}{x({{y}^{3}}-x)}\]and passing through the point (4, -2) is

A. \[{{y}^{2}}=-2x\]
B. \[y=-2x\]
C. \[{{y}^{3}}=-2x\]
D. None of these
Answer» D. None of these
1164.

The solution to of the differential equation \[(x+1)\frac{dy}{dx}-y={{e}^{3x}}{{(x+1)}^{2}}\] is

A. \[y=(x+1){{e}^{3x}}+c\]
B. \[3y=(x+1)+{{e}^{3x}}+c\]
C. \[\frac{3y}{x+1}={{e}^{3x}}+c\]
D. \[y{{e}^{-3x}}=3(x+1)+c\]
Answer» D. \[y{{e}^{-3x}}=3(x+1)+c\]
1165.

A function \[y=f(x)\] satisfies the condition \[f'(x)\sin x+f(x)\cos x=1\] being bounded when\[x\to 0\]. If\[l=\int_{0}^{\pi /2}{f(x)dx}\], then

A. \[\frac{\pi }{2}<l<\frac{{{\pi }^{2}}}{4}\]
B. \[\frac{\pi }{4}<l<\frac{{{\pi }^{2}}}{2}\]
C. \[1<l<\frac{\pi }{2}\]
D. \[0<l<1\]
Answer» B. \[\frac{\pi }{4}<l<\frac{{{\pi }^{2}}}{2}\]
1166.

Solution of differential equation \[{{x}^{2}}=1+{{\left( \frac{x}{y} \right)}^{-1}}\frac{dy}{dx}+\frac{{{\left( \frac{x}{y} \right)}^{-2}}{{\left( \frac{dy}{dx} \right)}^{2}}}{2!}\]\[+\frac{{{\left( \frac{x}{y} \right)}^{-3}}{{\left( \frac{dy}{dx} \right)}^{3}}}{3!}+.........\] is

A. \[{{y}^{2}}={{x}^{2}}(ln\,\,{{x}^{2}}-1)+C\]
B. \[y={{x}^{2}}(ln\,\,x-1)+C\]
C. \[{{y}^{2}}=x(ln\,\,x-1)+C\]
D. \[y={{x}^{2}}{{e}^{{{x}^{2}}}}+C\]  
Answer» B. \[y={{x}^{2}}(ln\,\,x-1)+C\]
1167.

The solution of the differential equation\[\frac{dy}{dx}=\frac{1-3y-3x}{1+x+y}\] is

A. \[x+y-\ell n\left| x+y \right|=c\]
B. \[3x+y+2\ell n\left| 1-x-y \right|=c\]
C. \[x+3y-2\ell n\left| 1-x-y \right|=c\]
D. None of these
Answer» C. \[x+3y-2\ell n\left| 1-x-y \right|=c\]
1168.

The solution to the differential equation\[\frac{dy}{dx}=\frac{yf'(x)-{{y}^{2}}}{f(x)}\] Where f(x) is a given function is

A. \[f(x)=y(x+c)\]
B. \[f(x)=cxy\]
C. \[f(x)=c(x+y)\]
D. \[yf(x)=cx\]
Answer» B. \[f(x)=cxy\]
1169.

The differential equation which represents the three parameter family of circles\[{{x}^{2}}+{{y}^{2}}+2gx+2fy+c=0\] is

A. \[y'''=\frac{3y'y'{{'}^{2}}}{1+y{{'}^{2}}}\]   
B. \[y'''=\frac{3y'{{'}^{2}}}{1+y{{'}^{2}}}\]
C. \[y'''=\frac{3y'}{1+y{{'}^{2}}}\]
D. \[y'''=\frac{3y'}{1-y{{'}^{2}}}\]
Answer» B. \[y'''=\frac{3y'{{'}^{2}}}{1+y{{'}^{2}}}\]
1170.

Given \[a=x/(y-z),\]\[b=y/(z-x)\]and \[c=z/(x-y),\] where x, y and z are not all zero, Then the value of \[ab+bc+ca\]

A. \[0\]
B. \[1\]
C. \[-1\]
D. None of these
Answer» D. None of these
1171.

\[A=\left| \begin{matrix}    2a & 3r & x  \\    4b & 6s & 2y  \\    -2c & -3t & -z  \\ \end{matrix} \right|=\lambda \left| \begin{matrix}    a & r & x  \\    b & s & y  \\    c & t & z  \\ \end{matrix} \right|,\] then what is the value of \[\lambda \]?

A. \[12\]
B. \[-12\]
C. \[7\]
D. \[-7\]
Answer» C. \[7\]
1172.

If \[A=\left[ \begin{matrix}    3 & 2  \\    1 & 4  \\ \end{matrix} \right],\] then what is A (adj A) equal to?

A. \[\left[ \begin{matrix}    0 & 10  \\    10 & 0  \\ \end{matrix} \right]\]
B. \[\left[ \begin{matrix}    10 & 0  \\    0 & 10  \\ \end{matrix} \right]\]
C. \[\left[ \begin{matrix}    1 & 10  \\    10 & 1  \\ \end{matrix} \right]\]
D. \[\left[ \begin{matrix}    10 & 1  \\    1 & 10  \\ \end{matrix} \right]\]
Answer» C. \[\left[ \begin{matrix}    1 & 10  \\    10 & 1  \\ \end{matrix} \right]\]
1173.

If A, B, and C are the angles of a triangle and \[\left| \begin{matrix}    1 & 1 & 1  \\    1+\sin A & 1+\sin B & 1+\sin C  \\    \sin A+{{\sin }^{2}}A & \sin B+{{\sin }^{2}}B & \sin C+{{\sin }^{2}}C  \\ \end{matrix} \right|=0,\]then the triangle must be

A. Isosceles
B. Equilateral
C. Right-angled
D. None of these
Answer» B. Equilateral
1174.

If in a triangle ABC, \[\left| \begin{matrix}    1 & \sin A & {{\sin }^{2}}A  \\    1 & \sin B & {{\sin }^{2}}B  \\    1 & \sin C & {{\sin }^{2}}C  \\ \end{matrix} \right|=0\] then the triangle is

A. Equilateral or isosceles
B. Equilateral or right-angled
C. Right angled or isosceles
D. None of these
Answer» B. Equilateral or right-angled
1175.

If \[f(x)=\left| \begin{matrix}    {{2}^{-x}} & {{e}^{x{{\log }_{e}}2}} & {{x}^{2}}  \\    {{2}^{-3x}} & {{e}^{3x{{\log }_{e}}2}} & {{x}^{4}}  \\    {{2}^{-5x}} & {{e}^{5x{{\log }_{e}}2}} & 1  \\ \end{matrix} \right|,\] then

A. \[f(x)+f(-x)=0\]
B. \[f(x)-f(-x)=0\]
C. \[f(x)+f(-x)=2\]
D. None of these
Answer» B. \[f(x)-f(-x)=0\]
1176.

If \[{{A}_{1}}{{B}_{1}}{{C}_{1}},\] \[{{A}_{2}}{{B}_{2}}{{C}_{2}}\] and \[{{A}_{3}}{{B}_{3}}{{C}_{3}}\]are three digit numbers, each of which is divisible by k, then \[\Delta =\left| \begin{matrix}    {{A}_{1}} & {{B}_{1}} & {{C}_{1}}  \\    {{A}_{2}} & {{B}_{2}} & {{C}_{2}}  \\    {{A}_{3}} & {{B}_{3}} & {{C}_{3}}  \\ \end{matrix} \right|\] is

A. Divisible by k
B. Divisible by \[{{k}^{2}}\]
C. Divisible by \[{{k}^{3}}\]
D. None of these
Answer» B. Divisible by \[{{k}^{2}}\]
1177.

If a, b, c are in GP, then what is the value of \[\left| \begin{matrix}    a & b & a+b  \\    b & c & b+c  \\    a+b & b+c & 0  \\ \end{matrix} \right|?\]

A. \[0\]
B. \[1\]
C. \[-1\]
D. None of these
Answer» B. \[1\]
1178.

The determinant \[\left| \begin{matrix}    a+b+c & a+b & a  \\    4a+3b+2c & 3a+2b & 2a  \\    10a+6b+3c & 6a+3b & 3a  \\ \end{matrix} \right|\] is independent of which one of the following?

A. a and b
B. b and c
C. a and c
D. All of these
Answer» C. a and c
1179.

The rank of the matrix \[\left[ \begin{matrix}    -1 & 2 & 5  \\    2 & -4 & a-4  \\    1 & -2 & a+1  \\ \end{matrix} \right]\] is

A. 1 if \[a=6\]
B. 2 if \[a=1\]
C. 3 if \[a=2\]
D. 1 if\[a=4\]
Answer» C. 3 if \[a=2\]
1180.

If \[\left| \begin{matrix}    a & \cot A/2 & \lambda   \\    b & \cot B/2 & \mu   \\    c & \operatorname{cotC}/2 & \gamma   \\ \end{matrix} \right|=0,\] where a, b, c, A, B, and C are elements of a triangle ABC with usual meaning. Then, the value of a \[(\mu -\gamma )+b(\gamma -\lambda )+c(\lambda -\mu )=0\] is

A. \[0\]
B. \[abc\]
C. \[ab+bc+ca\]
D. \[2abc\]
Answer» B. \[abc\]
1181.

If \[{{a}_{r}}={{(\cos 2r\pi +i\sin 2r\pi )}^{\frac{1}{9}}},\]then the value of \[\left| \begin{matrix}    {{a}_{1}} & {{a}_{2}} & {{a}_{3}}  \\    {{a}_{4}} & {{a}_{5}} & {{a}_{6}}  \\    {{a}_{7}} & {{a}_{8}} & {{a}_{9}}  \\ \end{matrix} \right|\] is

A. \[1\]
B. \[-1\]
C. \[0\]
D. None of these
Answer» D. None of these
1182.

If \[\omega \] is a complex cube root of unity, then value of\[\Delta =\left| \begin{matrix}    {{a}_{1}}+{{b}_{1}}\omega  & {{a}_{1}}{{\omega }^{2}}+{{b}_{1}} & {{c}_{1}}+{{b}_{1}}\bar{\omega }  \\    {{a}_{2}}+{{b}_{2}}\omega  & {{a}_{2}}{{\omega }^{2}}+{{b}_{2}} & {{c}_{2}}+{{b}_{2}}\bar{\omega }  \\    {{a}_{3}}+{{b}_{3}}\omega  & {{a}_{3}}{{\omega }^{2}}+{{b}_{3}} & {{c}_{3}}+{{b}_{3}}\bar{\omega }  \\ \end{matrix} \right|\] is

A. \[0\]
B. \[-1\]
C. \[2\]
D. None of these
Answer» B. \[-1\]
1183.

If \[\text{l}_{r}^{2}+m_{r}^{2}+n_{r}^{2}=\text{1};\] \[r=1,2,3\] and \[{{\text{l}}_{r}}{{\text{l}}_{s}}+{{m}_{r}}{{m}_{s}}+{{n}_{r}}{{n}_{s}}=0;\]\[r\ne s,\]\[r=1,2,3;\] \[s=1,2,3,\]then the value of \[\left| \begin{matrix}    {{\text{l}}_{1}} & {{m}_{1}} & {{n}_{1}}  \\    {{\text{l}}_{2}} & {{m}_{2}} & {{n}_{2}}  \\    {{\text{l}}_{3}} & {{m}_{3}} & {{n}_{3}}  \\ \end{matrix} \right|\] is

A. \[0\]
B. \[\pm 1\]
C. \[2\]
D. None of these
Answer» C. \[2\]
1184.

If \[{{a}_{1}},{{a}_{2}},{{a}_{3}},............\]are positive numbers in G.P. then the value of \[\left| \begin{matrix}    \log {{a}_{n}} & \log {{a}_{n+1}} & \log {{a}_{n+2}}  \\    \log {{a}_{n+1}} & \log {{a}_{n+2}} & {{\operatorname{loga}}_{n+3}}  \\    \log {{a}_{n+2}} & \log {{a}_{n+3}} & \log {{a}_{n+4}}  \\ \end{matrix} \right|\]

A. \[1\]
B. \[4\]
C. \[3\]
D. \[0\]
Answer» E.
1185.

If \[\left| A \right|=8,\] where.4 is square matrix of order 3, then what is \[\left| adj\,\,A \right|\] equal to?

A. \[16\]
B. \[24\]
C. \[64\]
D. \[512\]
Answer» D. \[512\]
1186.

Suppose the system of equations \[{{a}_{1}}x+{{b}_{1}}y+{{c}_{1}}z={{d}_{1}}\] \[{{a}_{2}}x+{{b}_{2}}y+{{c}_{2}}z={{d}_{2}}\] \[{{a}_{3}}x+{{b}_{3}}y+{{c}_{3}}z={{d}_{3}}\] has a unique solution \[({{x}_{0}},{{y}_{0}},{{z}_{0}})\]. If \[{{x}_{0}}=0,\] then which one of the following is correct?

A. \[\left| \begin{matrix}    {{a}_{1}} & {{b}_{1}} & {{c}_{1}}  \\    {{a}_{2}} & {{b}_{2}} & {{c}_{2}}  \\    {{a}_{3}} & {{b}_{3}} & {{c}_{3}}  \\ \end{matrix} \right|=0\]
B. \[\left| \begin{matrix}    {{d}_{1}} & {{b}_{1}} & {{c}_{1}}  \\    {{d}_{2}} & {{b}_{2}} & {{c}_{2}}  \\    {{d}_{3}} & {{b}_{3}} & {{c}_{3}}  \\ \end{matrix} \right|=0\]
C. \[\left| \begin{matrix}    {{d}_{1}} & {{a}_{1}} & {{c}_{1}}  \\    {{d}_{2}} & {{a}_{2}} & {{c}_{2}}  \\    {{d}_{3}} & {{a}_{3}} & {{c}_{3}}  \\ \end{matrix} \right|=0\]
D. \[\left| \begin{matrix}    {{d}_{1}} & {{a}_{1}} & {{b}_{1}}  \\    {{d}_{2}} & {{a}_{2}} & {{b}_{2}}  \\    {{d}_{3}} & {{a}_{3}} & {{b}_{3}}  \\ \end{matrix} \right|=0\]
Answer» C. \[\left| \begin{matrix}    {{d}_{1}} & {{a}_{1}} & {{c}_{1}}  \\    {{d}_{2}} & {{a}_{2}} & {{c}_{2}}  \\    {{d}_{3}} & {{a}_{3}} & {{c}_{3}}  \\ \end{matrix} \right|=0\]
1187.

Let A and B be two matrices of order\[n\times n\]. Let A be non-singular and B be singular. Consider the following: 1. AB is singular 2. AB is non-singular 3. \[{{A}^{-1}}B\] is singular 4.\[{{A}^{-1}}B\] is non singular Which of the above is/ are correct?

A. 1 and 3
B. 2 and 4 only
C. 1 only
D. 3 only
Answer» C. 1 only
1188.

If x, y, z are complex numbers, and\[\Delta =\left| \begin{matrix}    0 & -y & -z  \\    {\bar{y}} & 0 & -x  \\    {\bar{z}} & {\bar{x}} & 0  \\ \end{matrix} \right|\] then \[\Delta \] is

A. Purely real
B. Purely imaginary
C. Complex
D. 0
Answer» C. Complex
1189.

Let \[\Delta =\left| \begin{matrix}    1+{{x}_{1}}{{y}_{1}} & 1+{{x}_{1}}{{y}_{2}} & 1+{{x}_{1}}{{y}_{3}}  \\    1+{{x}_{2}}{{y}_{1}} & 1+{{x}_{2}}{{y}_{2}} & \,1+{{x}_{2}}{{y}_{3}}  \\    1+{{x}_{3}}{{y}_{1}} & 1+{{x}_{3}}{{y}_{2}} & 1+{{x}_{3}}{{y}_{3}}  \\ \end{matrix} \right|\] then value of \[\Delta \] is

A. \[{{x}_{1}}{{x}_{2}}{{x}_{3}}+{{y}_{1}}{{y}_{2}}{{y}_{3}}\]
B. \[{{x}_{1}}{{x}_{2}}{{x}_{3}}{{y}_{1}}{{y}_{2}}{{y}_{3}}\]
C. \[{{x}_{2}}{{x}_{3}}{{y}_{2}}{{y}_{3}}+{{x}_{3}}{{x}_{1}}{{y}_{3}}{{y}_{1}}+{{x}_{1}}{{x}_{2}}{{y}_{1}}{{y}_{2}}\]
D. 0
Answer» E.
1190.

If \[a>0,b>0,c>0\] are respectively the pth, qth,rth terms of GP, then the value of the determinant \[\left| \begin{matrix}    \log a & p & 1  \\    \log b & q & 1  \\    \log c & r & 1  \\ \end{matrix} \right|\] is

A. \[0\]
B. \[1\]
C. \[-1\]
D. None of these
Answer» B. \[1\]
1191.

The value of \[\left| \begin{matrix}    ^{10}{{C}_{4}} & ^{10}{{C}_{5}} & ^{11}{{C}_{m}}  \\    ^{11}{{C}_{6}} & ^{11}{{C}_{7}} & ^{12}{{C}_{m+2}}  \\    ^{12}{{C}_{8}} & ^{12}{{C}_{9}} & ^{13}{{C}_{m+4}}  \\ \end{matrix} \right|=0,\] when m is equal to

A. \[6\]
B. \[5\]
C. \[4\]
D. \[1\]
Answer» C. \[4\]
1192.

If \[A\left[ \begin{matrix}    1 & 2  \\    3 & 5  \\ \end{matrix} \right],\] then the value of the determinant \[|{{A}^{2009}}-5{{A}^{2008}}|\] is

A. \[-6\]
B. \[-5\]
C. \[-4\]
D. \[4\]
Answer» B. \[-5\]
1193.

If \[a,b,c,d>0,x\text{ }\in \text{R}\] and \[({{a}^{2}}+{{b}^{2}}+{{c}^{2}}){{x}^{2}}-2(ab+bc+cd)x+{{b}^{2}}+{{c}^{2}}+{{d}^{2}}\le 0.\]Then, \[\left| \begin{matrix}    33 & 14 & \log a  \\    65 & 27 & \log b  \\    97 & 40 & \log c  \\ \end{matrix} \right|\] is equal to

A. \[1\]
B. \[-1\]  
C. \[2\]
D. \[0\]
Answer» E.
1194.

If \[g(x)=\left| \begin{matrix}    {{a}^{-x}} & {{e}^{x{{\log }_{e}}a}} & {{x}^{2}}  \\    {{a}^{-3x}} & {{e}^{3x{{\log }_{e}}a}} & {{x}^{4}}  \\    {{a}^{-5x}} & {{e}^{5x{{\log }_{e}}a}} & 1  \\ \end{matrix} \right|,\] then

A. \[g(x)+g(-x)=0\]
B. \[g(x)-g(-x)=0\]
C. \[g(x)\times g(-x)=0\]
D. None of these
Answer» B. \[g(x)-g(-x)=0\]
1195.

Let A be an \[n\times n\] matrix. If \[\det \,(\lambda A)={{\lambda }^{s}}\det \,(A),\] what is the value of s?

A. \[0\]
B. \[1\]
C. \[-1\]
D. \[n\]
Answer» E.
1196.

If \[|{{A}_{n\times n}}|=3\] and \[|adj\,\,A|=243,\] what is the value of n?

A. \[4\]
B. \[5\]
C. \[6\]
D. \[7\]
Answer» D. \[7\]
1197.

Consider the following statements: 1. If det \[A=0,\]then det \[(adj\,A)=0\] 2. If A is non- singular, then \[\det \,({{A}^{-1}})={{(\det \,A)}^{-1}}\]

A. 1 only
B. 2 only
C. Both 1 and 2     
D. Neither 1 nor 2
Answer» D. Neither 1 nor 2
1198.

Let \[{{S}_{k}}={{\alpha }^{k}}+{{\beta }^{k}}+{{\gamma }^{k}},\] then \[\Delta =\left| \begin{matrix}    {{S}_{0}} & {{S}_{1}} & {{S}_{2}}  \\    {{S}_{1}} & {{S}_{2}} & {{S}_{3}}  \\    {{S}_{2}} & {{S}_{3}} & {{S}_{4}}  \\ \end{matrix} \right|\] is equal to

A. \[{{S}_{6}}\]
B. \[{{S}_{5}}-{{S}_{3}}\]
C. \[{{S}_{6}}-{{S}_{4}}\]
D. None
Answer» E.
1199.

If \[f(x)=\left| \begin{matrix}    1+{{\sin }^{2}}x & {{\cos }^{2}}x & 4\sin 2x  \\    {{\sin }^{2}}x & 1+{{\cos }^{2}}x & 4\sin 2x  \\    {{\sin }^{2}}x & {{\cos }^{2}}x & 1+4\sin 2x  \\ \end{matrix} \right|\]What is the maximum value of \[f(x)\]?

A. 2
B. 4
C. 6
D. 8
Answer» D. 8
1200.

If \[A=\left[ \begin{matrix}    a & 0 & 0  \\    0 & a & 0  \\    0 & 0 & a  \\ \end{matrix} \right],\] then the value of \[|adj\,\,A|\] is

A. \[{{a}^{27}}\]
B. \[{{a}^{9}}\]
C. \[{{a}^{6}}\]
D. \[{{a}^{2}}\]
Answer» D. \[{{a}^{2}}\]