Font size
WorksheetsMathematics 2 mid sem EC
Total questions: 65
Worksheet time: 2hrs 10mins
The order and degree of differential equation ((dx2)(d2y))2−[1−(dxdy)2]3=0 is
2 and 2
2 and 3
2 and 1
None of above
The general solution of differential equation dx2d2y−2 (dxdy)−3y=0 is
y=c1e3x+c2ex
y=c1e(−3x)+c2ex
y=c1e3x+c2e(−x)
y=c1e(−3x)+c2e(−x)
L−1{(s+a)21}
e(−at)
te(−at)
t2e(−at)
teat
The complete solution of Linear Differential equations involves
complete function + particular integral
complementary function + particular integral
complementary function + definite integral
complete function + indefinite integral
The complementary function of the equation dx2d2y+2dxdy+y=0 is
c1ex+c2e−x
c1e−x+c2e−x
c1ex+c2ex
(c1+c2x)e−x
If r = xi + yj + zk then div (r) is
3
1
r
0
Laplace Transform transforms a function from
f(t) to F(s)
F(s) to f(t)
f(t) to f′(t)
f"(t) to f′(t)
Define this property: L(f(t)eat)=F(s−a)
Linearity Property
First Shifting Property
Convolution Theorem
Second Shifting Property
Find L(e3t(t3−3t2+5t))
(s−3)42−⎝⎛((s−3)3)3⎠⎞+(s−3)25
(s−3)46−((s−3)36)+(s−3)25
(s−3)32−((s−3)(2)3)+s−35
None of the above
Find L(tsin 4t)
s2+42
−(s2+4)24s
−(s2+16)28s
None of the above
Find L−1(s2+25s)
cos 25t
sin 5t
cos 5t
sin 25t
L−1 (s2+254s+3(s2+1)2)
4 cos 25t+32sin t
cos 5t+ sin t
4 cos 5t +32sin t
None of the above
L−1(F(s−5))=e5tf(t) Based on first shifting property for Inverse Laplace transform, what is a value?
4
5
3
2
L−1((s−3)21)
e2tt
ett2
e3tt
t2e5t
L−1((s−4)2+16s)
e4t(cos 4t+sin 4t)
e2t(cos 2t+sin 2t)
e2t(4cos t+4sin t)
None of the above
L−1(s2+2s+5(s+2))
f(t)=e−tsin(2t)+e−tcos(2t)
f(t)=21e−tsin(2t)+e−tcos(2t)
f(t)=e−tsin(2t)+21e−tcos(2t)
None of the above
By convolution theorem, find Laplace Transform for X(s)=s(s2+4)1
2 1sin 2t
41cos 2t−4
41(1−cos 2t)
2 1cos 2t
Given g(t)=tf(t) , what is G(s)?
G(s)=∫s∞F(u)du
G(s)=(−1)dsdF(s)
G(s)=∫∞sF(u)du
G(s)=(−1)−1dsdF(s)
The particular integral of the equation (D3−1)y=(ex+1)2 is
7e−2x+32x−1
7e3x+32x−1
7e2x+35x−1
7e2x+32x−1
The P.I. of the equation (D3+D)y=cosx is
−2xcosx
2xcosx
−2cosx
−5xcosx
The C.F. of the equation (D2−9)y=e−3x+1+e3x is
c1e−3x+c2e−x
c1e3x+c2e3x
c1e3x+c2e−x
c1e3x+c2e−3x
dy2d2x+4dydx−6y=0
Which of the following options are TRUE about the above DE?
The roots of the auxiliary equations are two complex roots.
The auxiliary equation has two different roots.
The auxiliary equation has two equal roots.
The equation is non-homogeneous.
Determine the general solution of y"−2y′+5y=0
y=C1ex+C2xe2x
y=C1ex+C2e2x
y=C1excos2x+C2exsin2x
y=C1e2xcosx+C2e2xsinx
What is the integrating factor for the differential equation: x1dydx−1+x21y=x3
ln(x2)
−x21
−x1
x1
Which of the following statement is TRUE.
dydx−x2=ex is linear and its integrating factor is −x21.
dydx−4x=0 with condition y(1)=2 is linear and its solution is y=2x2.
dydx−x2=ex is linear and its solution is y=x21.
y3dx−4x2dy=0 is not exact.
By separation of variables, solve the resulting equations ∫ v+1vdv=∫ y1dy
yx−ln∣∣∣∣yx+1∣∣∣∣=lny+C
yx+ln∣∣∣∣yx+1∣∣∣∣=lny+C
yx+2y2x2=lny+C
yx−2y2x2=lny+C
State the order and degree for differential equation below: (dx2d2y)3+5(dxdy)4=cos3x
Order:2
Degree: 4
Order:3
Degree: 2
Order:2
Degree: 3
Order:4
Degree: 2
Form the differential equation of the curve:
y=Aex+Be−x
dx2d2y=y
dx2d2y+y=0
dx2d2y=Aex−Be−x
dx2d2y=Axex−Bxe−x
Mdx+Ndy=0 is the standard form of exact equation.
Which one is the TRUE statement for this exact equation: eydx+(xey+y)dy=0
∂x∂N=xey+1
∂y∂M=yey
∂y∂M=ey
None of the above
L−1((s−4)2+16s)
e4t(cos 4t+sin 4t)
e2t(cos 2t+sin 2t)
e2t(4cos t+4sin t)
None of the above
L−1(s2+2s+5(s+2))
f(t)=e−tsin(2t)+e−tcos(2t)
f(t)=21e−tsin(2t)+e−tcos(2t)
f(t)=e−tsin(2t)+21e−tcos(2t)
None of the above
Find the partial fraction for (s−2)(s−3)(2s−8)
s−22−s−34
s−23−s−32
s−24−s−32
None of the above
By convolution theorem, find F(s) and G(s) X(s)=s(s2+4)1
F(s)=s1;G(s)=s2+41
F(s)=s1;G(s)=s3+4s1
F(s)=s2+41;G(s)=s1
None of the above
Find curl F : F(x,y,z)=<x2, y−z, xey>
<xey+1, −ey, 0>
<xey+1, ey, 0>
<xey−1,−ey, 0>
<xey−1, ey, 0>
Find div F : F(x,y,z)=<x2, y−z, xey>
2x + 1
2x - 1
2x+xey
2x+1+xey
Determine the validity of the statements.
a) The divergence of a scalar valued function is vector valued function.
b) The curl of a vector valued function is vector valued function.
c) A vector f is solenoidal if div f=o.
d) A vector is called harmonic if curl f=o vector.
a and b are true
only d is true
b and c are true
only c is true
The vector f=(x2−yz)i+(y−zx)j+(z2−xy)k is
irrotational
solenoidal
linear
harmonic
If F is solenoidal vector then
∇×F =0
∇⋅F =0
∇F =0
None of the above
Laplace transform is an
differential transform
power series transform
integral transform
exponential transform
The divergence of F=xyzı^+zx2yȷ^+(3z2−y2z)k is
yz+zx+2xz
yz+3x2+(2xz−y2)
yz+xy
xy-yz
The value of λ so that the vector (x+3y)ı^+(y−2z)ȷ^+(x+λz)k^ is solenoidal vector is
-2
3
1
none
A differential equation of the form dxdy= N(x,y)M(x,y)
is called homogeneous if M(x,y)&N(x,y) are
Homogeneous functions of different degree
Homogeneous functions of same degree
Non-Homogeneous functions of different degree
Non-Homogeneous functions of same degree
The solution of the differential equation xdx+ydy=x2ydy−y2xdx is
x2−1=c(1+y2)
x2+1=c(1−y2)
x3−1=c(1+y3)
x3+1=c(1−y3)
Which of the following function can be used as an integrating factor to turn the following non-exact D.E. into an exact D.E.? (3ycosx−xysinx)+2xcosxdy/dx=0
x2
x2y
y2
xy2
The solution of the differential equation (cosx+ysinx)dx=cosxdy,y(π)=0 is
y=tanx+c
y=sinx2
y=sinx
y=tanx
Which of the following D.E. are non-exact D.E.?
yexdx+(2y+ex)dy=0
dy/dx=(x2−x−y2)/2xy
(y4+2y)dx+(xy3+2y4−4x)dy=0
After converting the D.E. (y4+2y)dx+(xy3+2y4−4x)dy=0 into an exact D.E., the value of
y+y2
y+y22
y−y2
y2+y22
Integrating factor of the differential equation (xy−2y2)dx−(x2−3xy)dy=0 is
xy21
xy2−1
x2y21
x2y1
The solution of D.E. (y−xp)(p−1)=p is
y=cx+c−1c
y2=cx+c−1c
y=cx2+c−1c
y=cx−c+1c
The solution of D.E. p=log(px−y) is
y=cx+ex
y=cx2+c
y=cx−ec
y=cx
The solution of D.E. y=px+p−p2 is
y=cx2
y=cx+c2
y=cx−c+c2
y=cx+c−c2
An equation of the form y=px+f(p) is known as
Bernoulli’s equation
Lagrange’s equation
Clairaut’s equation
None of these
Laplace transform if cos(at) u(t) is
a2+s2s
a2 + s2a
s2 +a2s2
s2+a2a2
The solution of D.E. (x2D2+xD−4)y=0 is
y= c1x2+ c2x−2
y= (c1+c2)x−2
y = c!e2x+c2e−2x
y=(c!+c2x)e−2x
The general solution of (4D2+12D+9)y=144e−3x is
y=(c1+c2x)e−23x−16e−3x
y=(c1+c2x)e−23x+ 8e3x
y=(c1+c2x)e−23x−8e−3x
y=(c1+c2x)e−23x+16e−3x
The P.I. of (x2D2−3xD+5)y = sin(log x) is
y=81(sin(logx)+cos(logx))
y=81(sin(logx)+cos x)
y=81(sinx+cos(logx))
None
The solution of (D4−D3−9D2−11D−4)y=0 is
y=c1e2x+c2e−2x+c3ex+c4e−x
y=c1e4x+(c2+c3x+c4x2)e−x
y=c1ex+c2e−2x+c3e3x+c4e−4x
y=(c1+c2x)e−2x+c3ex+c4e−x
The general solution of (D2+4D+4)y=2 sinh 2x is
y=(c1+c2x)e−2x+16e2x−2x2e−2x
y=(c1+c2x)e−6x+136e2x−12x2e−2x
y=(c1+c2x)e−2x+16e2x−x2
y=(c1+c2x)e−2x−2x2e−2x
L−1(s524) is t4 . What is L−1(s(5)1) ?
s524
241t4
241t5
None
if ∅=2x2+3y2
then
the value of
∣grad ϕ∣ at (1, 3) is
213
5
5
213
Write your fullname
WRITE YOUR
ENROLLMENT NO.
WRITE YOUR EMAIL ID
WRITE YOUR MOBILE NUMBER
WRITE YOUR PARENT'S MOBILE NUMBER
