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This section includes 88 Mcqs, each offering curated multiple-choice questions to sharpen your BITSAT knowledge and support exam preparation. Choose a topic below to get started.
1. |
For \(\frac{{{d^2}y}}{{d{x^2}}} + 4\frac{{dy}}{{dx}} + 3y = 3{e^{2x}}\), the particular integral is : |
A. | \(\frac{1}{{15}}{e^{2x}}\) |
B. | \(\frac{1}{5}{e^{2x}}\) |
C. | \(3{e^{2x}}\) |
D. | \({C_1}{e^{ - x}} + {C_2}{e^{ - 3x}}\) |
Answer» C. \(3{e^{2x}}\) | |
2. |
Consider the differential equation given below:\(\dfrac{dy}{dx} + \dfrac{x}{1-x^2} y= x\sqrt{y}\)The integrating factor of the differential equation is: |
A. | (1 - x2)-1/4 |
B. | (1 - x2)-1/2 |
C. | (1 - x2)-3/4 |
D. | (1 - x2)-3/2 |
Answer» B. (1 - x2)-1/2 | |
3. |
General solution of the equation (x3 + 3xy2)dx + (3x2y + y3)dy = 0 is (c is a constant) |
A. | \(\frac{1}{4}\left( {{x^4} + 6{x^2}{y^2} + {y^4}} \right) = c\) |
B. | \(\frac{1}{5}\left( {8{x^4} + 6{x^3}y + {y^3}} \right) = c\) |
C. | \(\frac{1}{{12}}\left( {{x^3} + 6x{y^2} + {y^4}} \right) = c\) |
D. | (x2 + y2) = c |
Answer» B. \(\frac{1}{5}\left( {8{x^4} + 6{x^3}y + {y^3}} \right) = c\) | |
4. |
For the equation \(\frac{{dy}}{{dx}} + 7{x^2}y = 0\), if y(0) = \(\frac{{3}}{{7}}\), then the value of y(1) is |
A. | \(\frac{7}{3}{e^{ - \frac{7}{3}}}\) |
B. | \(\frac{7}{3}{e^{ - \frac{3}{7}}}\) |
C. | \(\frac{3}{7}{e^{ - \frac{7}{3}}}\) |
D. | \(\frac{3}{7}{e^{ - \frac{3}{7}}}\) |
Answer» D. \(\frac{3}{7}{e^{ - \frac{3}{7}}}\) | |
5. |
If \(\rm \dfrac{d^2y}{dx^2}+\sin x = 0\), then the solution of this differential equation is - |
A. | \(\rm y=\sin x + c_1 x+c_2\) |
B. | \(\rm y=\cos x+c_1 x^2+c_2\) |
C. | \(\rm y=\tan x+ c\) |
D. | \(\rm y=\log \sin x + cx\) |
Answer» B. \(\rm y=\cos x+c_1 x^2+c_2\) | |
6. |
\(\frac{{{\partial ^2}u}}{{\partial {t^2}}} = {c ^2}\frac{{{\partial ^2}u}}{{\partial {x^2}}}\) represents the equation for |
A. | Vibration of a stretched string |
B. | Heat flow of a thin rod |
C. | Motion of a projectile in a gravitational field |
D. | Oscillation of a simple pendulum |
Answer» B. Heat flow of a thin rod | |
7. |
Consider the following partial differential equation for with the constant c > 1:Solution of this equation is \(\frac{{\partial u}}{{\partial y}} + c\frac{{\partial u}}{{\partial x}} = 0\) |
A. | u(x,y) = f(x + cy) |
B. | u(x, y) = f(x – cy) |
C. | u(x, y) = f(cx + y) |
D. | u(x,y) = f(cx – y) |
Answer» C. u(x, y) = f(cx + y) | |
8. |
Determine the degree and order of the given differential equation respectively. \({\rm{y}} = {\rm{x}}{\left( {\frac{{{\rm{dy}}}}{{{\rm{dx}}}}} \right)^2} + {\left( {\frac{{{\rm{dx}}}}{{{\rm{dy}}}}} \right)^2}?\) |
A. | 1, 2 |
B. | 2, 1 |
C. | 1, 4 |
D. | 4, 1 |
Answer» E. | |
9. |
If the characteristic equation of the differential equation \(\frac{{{d^2}y}}{{d{x^2}}} + 2\alpha \frac{{dy}}{{dx}} + y = 0\) has two equal roots, then the values of α are |
A. | ± 1 |
B. | 0, 0 |
C. | ± j |
D. | ± 1/2 |
Answer» B. 0, 0 | |
10. |
A particle starts from origin with a velocity (in m/s) given by the equation \(\rm \frac{dx}{dt}=x+1\). The time (in seconds) taken by the particle to traverse a distance of 24 m is: |
A. | ln 24 |
B. | ln 5 |
C. | 2 ln 5 |
D. | 2 ln 4 |
Answer» D. 2 ln 4 | |
11. |
A one-dimensional domain is discretized into N sub-domains of width Dx with node numbers i = 0, 1, 2, 3…………, N. If the time scale is discretized in steps of Dt, the forward-time and centered-space finite difference approximation at ith node and nth time step, for the partial differential equation \(\frac{{\partial v}}{{\partial t}} = \beta \frac{{{\partial ^2}v}}{{\partial {x^2}}}\) is |
A. | \(\frac{{V_{i + 1}^{\left( {n + 1} \right)} - V_i^{\left( N \right)}}}{{{\rm{\Delta }}t}} = \beta \left[ {\frac{{V_{i + 1}^{\left( n \right)} - 2V_i^{\left( n \right)} + V_{i - 1}^{\left( n \right)}}}{{2{\rm{\Delta }}x}}} \right]\) |
B. | \(\frac{{V_i^{\left( n \right)} - V_i^{\left( {n - 1} \right)}}}{{2{\rm{\Delta }}t}} = \beta \left[ {\frac{{V_{i + 1}^{\left( n \right)} - 2V_i^{\left( n \right)} + V_{i - 1}^{\left( n \right)}}}{{2{\rm{\Delta }}x}}} \right]\) |
C. | \(\frac{{V_i^{\left( {n + 1} \right)} - V_i^{\left( n \right)}}}{{{\rm{\Delta }}t}} = \beta \left[ {\frac{{V_{i + 1}^{\left( n \right)} - 2V_i^{\left( n \right)} + V_{i - 1}^{\left( n \right)}}}{{{{\left( {{\rm{\Delta }}x} \right)}^2}}}} \right]\) |
D. | \(\frac{{V_i^{\left( n \right)} - V_i^{\left( n \right)}}}{{{\rm{\Delta }}t}} = \beta \left[ {\frac{{V_{i + 1}^{\left( n \right)} - 2V_i^{\left( n \right)} + V_{i - 1}^{\left( n \right)}}}{{{{\left( {{\rm{\Delta }}x} \right)}^2}}}} \right]\) |
Answer» D. \(\frac{{V_i^{\left( n \right)} - V_i^{\left( n \right)}}}{{{\rm{\Delta }}t}} = \beta \left[ {\frac{{V_{i + 1}^{\left( n \right)} - 2V_i^{\left( n \right)} + V_{i - 1}^{\left( n \right)}}}{{{{\left( {{\rm{\Delta }}x} \right)}^2}}}} \right]\) | |
12. |
If y = sin (ln x), then which one of the following is correct? |
A. | \(\frac{{{d^2}y}}{{d{x^2}}} + y = 0\) |
B. | \(\frac{{{d^2}y}}{{d{x^2}}} = 0\) |
C. | \({x^2}\frac{{{d^2}y}}{{d{x^2}}} + x\frac{{dy}}{{dx}} + y = 0\) |
D. | \({x^2}\frac{{{d^2}y}}{{d{x^2}}} - x\frac{{dy}}{{dx}} + y = 0\) |
Answer» D. \({x^2}\frac{{{d^2}y}}{{d{x^2}}} - x\frac{{dy}}{{dx}} + y = 0\) | |
13. |
Consider the following statements:1. The general solution of \(\frac{{{\rm{dy}}}}{{{\rm{dx}}}} = {\rm{f}}\left( {\rm{x}} \right) + {\rm{x}}\) is of the form y = g(x) + c, where c is an arbitrary constant.2. The degree of \({\left( {\frac{{{\rm{dx}}}}{{{\rm{dy}}}}} \right)^2} = {\rm{f}}\left( {\rm{x}} \right)\) is 2.Which of the above statements is/are correct? |
A. | 1 only |
B. | 2 only |
C. | Both 1 and 2 |
D. | Neither 1 nor 2 |
Answer» D. Neither 1 nor 2 | |
14. |
Consider the following in respect of the differential equation:\(\frac{{{d^2}y}}{{d{x^2}}} + 2{\left( {\frac{{dy}}{{dx}}} \right)^2} + 9y = x\)1. The degree of the differential equation is 1.2. The order of the differential equation is 2.Which of the above statements is/are correct? |
A. | 1 only |
B. | 2 only |
C. | Both 1 and 2 |
D. | Neither 1 nor 2 |
Answer» D. Neither 1 nor 2 | |
15. |
If \(u = \sin^{-1} \left(\dfrac{x}{y}\right) + \tan^{-1} \left(\dfrac{y}{x}\right)\), then the value of \(x \dfrac{\partial u}{\partial x} + y \dfrac{\partial u}{\partial y}\) is |
A. | U |
B. | 2u |
C. | 3u |
D. | 0 |
Answer» E. | |
16. |
Consider the following differential equation:\(x\left( {ydx + xdy} \right)\cos \frac{y}{x} = y\left( {xdy - ydx} \right)\sin \frac{y}{x}\)Which of the following is the solution of the above equation (c is an arbitrary constant)? |
A. | \(\frac{x}{y}\cos \frac{y}{x} = c\) |
B. | \(\frac{x}{y}\sin \frac{y}{x} = c\) |
C. | \(xy\cos \frac{y}{x} = c\) |
D. | \(xy\sin \frac{y}{x} = c\) |
Answer» D. \(xy\sin \frac{y}{x} = c\) | |
17. |
A complete solution of partial differential equation\(x\;\frac{{\partial z}}{{\partial x}} + y\frac{{\partial z}}{{\partial y}} - z = \frac{{\partial z}}{{\partial x}}\frac{{\partial z}}{{\partial y}}\) will be: |
A. | z = ax + by - ab, where a, b are arbitrary constants. |
B. | z = x2 + y2 - 2ab, where ab b are arbitrary constants. |
C. | z = ax2 + by2 + abxy, where a, b are arbitrary constants. |
D. | z = ax - by + ab, where a, b are arbitrary constants. |
Answer» B. z = x2 + y2 - 2ab, where ab b are arbitrary constants. | |
18. |
It is given that y” + 2y’ + y = 0, y(0) = 0, y(1) = 0. What is y(0.5) ? |
A. | 0 |
B. | 0.37 |
C. | 0.62 |
D. | 1.13 |
Answer» B. 0.37 | |
19. |
Euler’s equation is |
A. | \(\frac{{dp}}{{\rho}}-gdz\;+\;vdv=0\) |
B. | \(\frac{{dp}}{{\rho}}+gdz\;+\;vdv=0\) |
C. | ρdp + gdz + vdv = 0 |
D. | none of these |
Answer» C. ρdp + gdz + vdv = 0 | |
20. |
Consider the following differential equation\((1 + y) \frac{dy}{dx} = y\)The solution of the equation that satisfies the condition y(1) = 1 is |
A. | (1 + y)ey = 2ex |
B. | yey = ex |
C. | y2ey = ex |
D. | 2yey = ex + e |
Answer» C. y2ey = ex | |
21. |
General solution of the differential equation (D2 - 2D + 1) y = ex is |
A. | \(A{e^x} + B{e^{ - x}} + \frac{{{x^2}}}{2}{e^x}\) |
B. | \({e^x}\left( {A + Bx} \right) - \frac{{{x^2}}}{2}{e^x}\) |
C. | \(A{e^x} + B{e^{ - x}} - \frac{{{x^2}}}{2}{e^x}\) |
D. | \({e^x}\left( {A + Bx} \right) + \frac{{{x^2}}}{2}{e^x}\) |
Answer» E. | |
22. |
If \(U = \mathop e\nolimits^{\frac{{\mathop x\nolimits^2 }}{{\mathop y\nolimits^2 }}} + \mathop e\nolimits^{\frac{{\mathop y\nolimits^2 }}{{\mathop x\nolimits^2 }}} \)then \(x\frac{{\partial u}}{{\partial x}} + y\frac{{\partial u}}{{\partial y}}\)is |
A. | u |
B. | 0 |
C. | \(\frac{1}{y}\mathop e\nolimits^{\frac{{\mathop x\nolimits^2 }}{{\mathop y\nolimits^2 }}} + \frac{1}{x}\mathop e\nolimits^{\frac{{\mathop y\nolimits^2 }}{{\mathop x\nolimits^2 }}} \) |
D. | \(\frac{{\mathop \partial \nolimits^2 u}}{{\partial x\partial y}}\) |
Answer» C. \(\frac{1}{y}\mathop e\nolimits^{\frac{{\mathop x\nolimits^2 }}{{\mathop y\nolimits^2 }}} + \frac{1}{x}\mathop e\nolimits^{\frac{{\mathop y\nolimits^2 }}{{\mathop x\nolimits^2 }}} \) | |
23. |
If x dy = y dx + y2 dy, y > 0 and y (1) = 1, then what is y (-3) equal to? |
A. | 3 only |
B. | -1 only |
C. | Both -1 and 3 |
D. | Neither -1 nor 3 |
Answer» B. -1 only | |
24. |
Consider two differential equations:I: ey dx + (xey + 2y)dy = 0II: xdy + 2y2 dx = 0Which of the following statements is correct? |
A. | Both I and II are exact differential equation. |
B. | I is not exact but Ii is an exact differential equation. |
C. | Neither I nor II are exact differential equations |
D. | I is exact but II is not an exact differential equation. |
Answer» E. | |
25. |
A function \(y\left( t \right)\) such that y(0) = 1 and y(1) = 3e-1, is a solution of the differential equation\(\frac{{{d^2}y}}{{d{t^2}}} + 2\frac{{dy}}{{dt}} + y = 0\;\). Then \(y\left( 2 \right)\) is |
A. | \(5{e^{ - 1}}\) |
B. | \(5{e^{ - 2}}\) |
C. | \(7{e^{ - 1}}\) |
D. | \(7{e^{ - 2}}\) |
Answer» C. \(7{e^{ - 1}}\) | |
26. |
If \(3e^x\ tan\ ydx + (1-e^x)sec^2\ ydy = 0\),then y is |
A. | tan y = c(1 + ex)3 |
B. | y = c(1 - ex)3 |
C. | log y = c(1 + ex)3 |
D. | tan y = c(1 - ex)3 |
Answer» E. | |
27. |
Consider the differential equation \({x^2}\frac{{{d^2}y}}{{d{x^2}}} + x\frac{{dy}}{{dx}} - y = 0\). Which of the following is a solution to this differential equation for x > 0? |
A. | ex |
B. | x2 |
C. | 1/x |
D. | In x |
Answer» D. In x | |
28. |
Differential equation \(y^3\frac{dy}{dx}\;+\;x^3=0\), y(0) = 1 has a solution given by y. The value of y(-1) is: |
A. | -1 |
B. | 0 |
C. | 1 |
D. | 2 |
Answer» C. 1 | |
29. |
In the following partial differential equation, θ is a function of t and z, and D and K are functions of θ\(D\left( \theta \right)\frac{{{\delta ^2}\theta }}{{\delta {z^2}}} + \frac{{\delta K\left( \theta \right)}}{{\delta z}} - \frac{{\delta \theta }}{{\delta t}} = 0\)The above equation is |
A. | a second order linear equation |
B. | a second degree linear equation |
C. | a second order non-linear equation |
D. | a second degree non-linear equation |
Answer» D. a second degree non-linear equation | |
30. |
Consider two solutions x(t) = x1(t) and x(t) = x2(t) of the differential equation \(\frac{{{d^2}x\left( t \right)}}{{d{t^2}}} + x\left( t \right) = 0,\;t > 0\), such that\(\ x_{1}(0)=1,\ {\left. {\frac{{d{x_1}\left( t \right)}}{{dt}}} \right|_{t = 0}} = 0,\;{x_2}\left( 0 \right) = 0,{\left. {\frac{{d{x_2}\left( t \right)}}{{dt}}} \right|_{t = 0}} = 1\)The Wronskian \(W\left( t \right) = \left| {\begin{array}{*{20}{c}} {{x_1}\left( t \right)}&{{x_2}\left( t \right)}\\ {\frac{{d{x_1}\left( t \right)}}{{dt}}}&{\frac{{d{x_2}\left( t \right)}}{{dt}}} \end{array}} \right|\) at \(t = \frac{\pi}{2}\) is |
A. | 1 |
B. | -1 |
C. | 0 |
D. | π/2 |
Answer» B. -1 | |
31. |
Consider a function u which depends on position x and time t. The partial differential Equation \(\frac{{\partial u}}{{\partial t}} = \frac{{{\partial ^2}u}}{{\partial {x^2}}}\) is known as the: |
A. | Wave equation |
B. | Heat equation |
C. | Laplace equation |
D. | Elasticity equation |
Answer» C. Laplace equation | |
32. |
For the Ordinary Differential Equation \(\frac{{{d^2}x}}{{d{t^2}}} - 5\frac{{dx}}{{dt}} + 6x = 0,\) with initial conditions x(0) = 0 and \(\frac{{dx}}{{dt}}\left( 0 \right) = 10,\) the solution is |
A. | -5e2t +6e3t |
B. | 5e2t = + 6e3t |
C. | -10e2t + 10e3t |
D. | 10e2t + 10e+3t |
Answer» D. 10e2t + 10e+3t | |
33. |
Consider the differential equation \(\frac{{dy}}{{dx}} = \left( {1 + {y^2}} \right)x\). The general solution with constant C is |
A. | \(y = \tan \frac{{{x^2}}}{2} + tanc\) |
B. | \(y = {\tan ^2}\left( {\frac{x}{2} + c} \right)\) |
C. | \(y = {\tan ^2}\left( {\frac{x}{2}} \right) + c\) |
D. | \(y = \tan \left( {\frac{{{x^2}}}{2} + c} \right)\) |
Answer» E. | |
34. |
If y = a cos 2x + b sin 2x, then |
A. | \(\frac{{{d^2}y}}{{d{x^2}}} + y = 0\) |
B. | \(\frac{{{d^2}y}}{{d{x^2}}} + 2y = 0\) |
C. | \(\frac{{{d^2}y}}{{d{x^2}}} - 4y = 0\) |
D. | \(\frac{{{d^2}y}}{{d{x^2}}} + 4y = 0\) |
Answer» E. | |
35. |
If u = xy choose the correct option |
A. | \(\frac{{{\partial ^3}u}}{{\partial {x^2}\partial y}} = \frac{{{\partial ^3}u}}{{\partial x\partial y\partial x}}\) |
B. | \(\frac{{{\partial ^3}u}}{{\partial x\partial {y^2}}} = \frac{{{\partial ^3}u}}{{\partial y\partial x\partial y}}\) |
C. | \(\frac{{{\partial ^3}u}}{{\partial x\partial {y^2}}} = \frac{{{\partial ^3}u}}{{\partial {x^2}\partial y}}\) |
D. | \(\frac{{{\partial ^2}u}}{{\partial {x^2}}} = \frac{{{\partial ^2}u}}{{\partial {y^2}}}\) |
Answer» B. \(\frac{{{\partial ^3}u}}{{\partial x\partial {y^2}}} = \frac{{{\partial ^3}u}}{{\partial y\partial x\partial y}}\) | |
36. |
If \(\rm z = \cos \left( {\frac{x}{y}} \right) + \sin \left( {\frac{x}{y}} \right)\)then \(x\frac{{\partial z}}{{\partial x}} + y\frac{{\partial z}}{{\partial y}} = \) |
A. | 1 |
B. | cos x |
C. | sin y |
D. | 0 |
Answer» E. | |
37. |
Consider the following equations\(\frac{{\partial V\left( {x,y} \right)}}{{\partial x}} = p{x^2} + {y^2} + 2xy\)\(\frac{{\partial V\left( {x,y} \right)}}{{\partial y}} = {x^2} + q{y^2} + 2xy\)Where p and q are constants. V (x, y) that satisfies the above equations is |
A. | \(p\frac{{{x^3}}}{3} + q\frac{{{y^3}}}{3} + 2xy + 6\) |
B. | \(p\frac{{{x^3}}}{3} + q\frac{{{y^3}}}{3} + 5\) |
C. | \(p\frac{{{x^3}}}{3} + q\frac{{{y^3}}}{3} + {x^2}y + x{y^2} + xy\) |
D. | \(p\frac{{{x^3}}}{3} + q\frac{{{y^3}}}{3} + {x^2}y + x{y^2}\) |
Answer» E. | |
38. |
Consider the differential equation \({x^2}\frac{{{d^2}y}}{{d{x^2}}} + x\frac{{dy}}{{dx}} - 4y = 0\) with the boundary conditions of y(0) = 0 and y(1) = 1. The complete solution of the differential equation is |
A. | x2 |
B. | \(\sin \left( {\frac{{\pi x}}{2}} \right)\) |
C. | \({e^x}\sin \left( {\frac{{\pi x}}{2}} \right)\) |
D. | \({e^{ - x}}\sin \left( {\frac{{\pi x}}{2}} \right)\) |
Answer» B. \(\sin \left( {\frac{{\pi x}}{2}} \right)\) | |
39. |
A first order differential is given by \(\frac{{dy}}{{dx}} = {e^{ - 3x}}\) Find the possible solution out of the following assuming K as constant. |
A. | e3x + K |
B. | \(- \frac{1}{3}{e^{ - 3x}} + K\) |
C. | \(- \frac{1}{3}{e^{3x}} + K\) |
D. | -3e3x + K |
Answer» C. \(- \frac{1}{3}{e^{3x}} + K\) | |
40. |
If \({I_n} = \mathop \smallint \limits_0^{\pi /4} {\tan ^n}\theta d\theta\) then the following reduction formula exists: |
A. | \({I_n} + {I_{n - 2}} = \frac{1}{{n - 1}}\) |
B. | \({I_n} + {I_{n - 2}} + \frac{1}{{n + 1}} = 0\) |
C. | \({I_n} - {I_{n - 2}} = \frac{1}{{n + 1}}\) |
D. | \({I_n} - {I_{n - 2}} + \frac{1}{{n - 1}} = 0\) |
Answer» B. \({I_n} + {I_{n - 2}} + \frac{1}{{n + 1}} = 0\) | |
41. |
Determine the partial-fraction expansion for:\(TF,\;G\;\left( s \right) = \frac{{32}}{{s\left( {s + 4} \right)\left( {s + 8} \right)}}\) |
A. | \(\frac{1}{s} + \frac{{ - 1}}{{s + 4}} + \frac{2}{{s + 8\;}}\) |
B. | \(\frac{1}{s} + \frac{2}{{s + 4\;}} + \frac{1}{{s + 8\;}}\) |
C. | \(\frac{1}{s} + \frac{{ - 1}}{{s + 4}} + \frac{1}{{s + 8}}\) |
D. | \(\frac{1}{s} + \frac{{ - 2}}{{s + 4\;}} + \frac{1}{{s + 8\;}}\) |
Answer» E. | |
42. |
Every Cauchy sequence is |
A. | Unbounded |
B. | Bounded |
C. | Infinite |
D. | None of these |
Answer» C. Infinite | |
43. |
Consider the differential equation \(\left( {{t^2} - 81} \right)\frac{{dy}}{{dt}} + 5ty = \sin \left( t \right)\) with y(1) = 2π. There exists a unique solution for this differential equation when t belongs to the interval |
A. | (–2, 2) |
B. | (–10, 10) |
C. | (–10, 2) |
D. | (0, 10) |
Answer» B. (–10, 10) | |
44. |
If integrating factor of x(1 - x2) dy + (2x2y - y - ax3) dx = 0 is \({e^{\int {Pdx} }}\), then P is equal to |
A. | \(\frac{{2{x^2} - a{x^3}}}{{x(1 - {x^2})}}\) |
B. | 2x3 - 1 |
C. | \(\frac{{2{x^2} - 1}}{{a{x^3}}}\) |
D. | \(\frac{{2{x^2} - 1}}{{x(1 - {x^2})}}\) |
Answer» E. | |
45. |
Find solution of the differential equation \(\rm xdy+ydx\over y\) = 0 |
A. | xy - c = 0 |
B. | y - cx = 0 |
C. | y - cx2 = 0 |
D. | x - cy2 = 0 |
Answer» B. y - cx = 0 | |
46. |
Order of the partial differential equation is |
A. | the order of the highest derivative appears in it |
B. | the order of the lowest derivative appears in it |
C. | the order of any derivative appears in it |
D. | none of these |
Answer» B. the order of the lowest derivative appears in it | |
47. |
An ordinary differential equation is given below \(6\frac{{{d^2}y}}{{d{x^2}}} + \frac{{dy}}{{dx}} - y = 0\) The general solution of the above equation (with constants C1 and C2), is |
A. | \(y\left( x \right) = \;{C_1}{e^{ - \frac{x}{3}}} + {C_2}{e^{\frac{x}{2}}}\) |
B. | \(y\left( x \right) = \;{C_1}{e^{\frac{x}{3}}} + {C_2}{e^{ - \frac{x}{2}}}\) |
C. | \(y\left( x \right) = \;{C_1}x{e^{ - \frac{x}{3}}} + {C_2}{e^{\frac{x}{2}}}\) |
D. | \(y\left( x \right) = \;{C_1}{e^{ - \frac{x}{3}}} + {C_2}x{e^{\frac{x}{2}}}\) |
Answer» C. \(y\left( x \right) = \;{C_1}x{e^{ - \frac{x}{3}}} + {C_2}{e^{\frac{x}{2}}}\) | |
48. |
A simple mass-spring oscillatory system consists of a mass m, suspended from a spring of stiffness k. Considering z as the displacement of the system at any time t, the equation of motion for the free vibration of the system is \(m\ddot z + kz = 0\). The natural frequency of the system is |
A. | \(\frac{k}{m}\) |
B. | \(\sqrt {\frac{m}{k}}\) |
C. | \(\sqrt {\frac{k}{m}}\) |
D. | \(\frac{m}{k}\) |
Answer» D. \(\frac{m}{k}\) | |
49. |
If a particular integral of the differential equation \((D^2+2D-1)y=e^{ax}\) is \(\frac{{ - 4}}{7}{e^{ax}}\), then the value of 'a' is |
A. | \(\left( {\frac{1}{2}~or~\frac{3}{2}} \right)\) |
B. | \(\left( {\frac{{ - 1}}{2}~or~\frac{{ - 3}}{2}} \right)\) |
C. | \(\left( {\frac{1}{2}~or~\frac{{ - 3}}{2}} \right)\) |
D. | \(\left( {\frac{{ - 1}}{2}~or~\frac{3}{2}} \right)\) |
Answer» C. \(\left( {\frac{1}{2}~or~\frac{{ - 3}}{2}} \right)\) | |
50. |
Find the solution of the differential equation \(\frac{dy}{dx}+2y=1\) such that y(0) = 0. |
A. | \(\frac{1-~{{e}^{-2x}}}{2}\) |
B. | \(\frac{1+~{{e}^{-2x}}}{2}\) |
C. | y = 1 + ex |
D. | \(\frac{1-{{e}^{-x}}}{2}\) |
Answer» B. \(\frac{1+~{{e}^{-2x}}}{2}\) | |