JNTU

JNTU B.Tech I Year MATHEMATICAL METHODS Previous Question Paper (August - 2018 - R15)

B.Tech | I Year | I-I | R15 | August - 2018

Answer PaperPaper Code: 121ALMaximum Marks: 75Time: 3 hours

Note: This question paper contains two parts A and B. Part A is compulsory which carries 25 marks. Answer all questions in Part A. Part B consists of 5 Units. Answer any one full question from each unit. Each question carries 10 marks and may have a, b, c as sub questions.

Part A

125 marks
a

Construct the forward difference table for the following data.

x12345
y4133473136
2 marks

Answer

xyΔyΔ2yΔ3yΔ4y
14
9
21312
216
334180
396
47324
63
5136
b

Write the normal equations to fit a curve of the form

y = a + bx + cx2
for the data (xi, yi), i = 1, 2, ..., n.

3 marks

Answer

The normal equations for the curve y = a + bx + cx2 are obtained by minimizing the sum of squares of residuals:

Σy = na + bΣx + cΣx2
Σxy = aΣx + bΣx2 + cΣx3
Σx2y = aΣx2 + bΣx3 + cΣx4
c

Derive the Newton-Raphson iterative formula to find

√N
, N > 0.

2 marks

Answer

Sign in to view the complete answer paper.

d

Evaluate

∫01 x3 dx
using Trapezoidal rule with h = 1/4.

3 marks

Answer

Sign in to view the complete answer paper.

e

Determine the Fourier coefficient a0 in the Fourier series of

f(x) = sin x
in [-π, π].

2 marks

Answer

Sign in to view the complete answer paper.

f

Find the Fourier sine transform of

f(x) = e-x
.

3 marks

Answer

Sign in to view the complete answer paper.

g

Obtain a partial differential equation by eliminating the arbitrary function ‘f’ from

z = f(x2+y2)
.

2 marks

Answer

Sign in to view the complete answer paper.

h

Solve

p + q = z
.

3 marks

Answer

Sign in to view the complete answer paper.

i

Find the unit normal vector to the surface

x2 + y2 + z2 = 3
at (2, 1, -3).

2 marks

Answer

Sign in to view the complete answer paper.

j

State Stoke’s theorem.

3 marks

Answer

Sign in to view the complete answer paper.

Part B

210 marks
a

Find the cubic polynomial which takes the values y(0)=1, y(1)=0, y(2)=1 and y(3)=10.

5 marks

Answer

Sign in to view the complete answer paper.

b

Using Lagrange’s formula to find y(10) from the data given below.

x56911
y12131416
5 marks

Answer

Sign in to view the complete answer paper.

OR
310 marks
a

Using the method of least squares, fit a straight line of the form y = ax + b for the following data.

x1234
y0112
5 marks

Answer

Sign in to view the complete answer paper.

b

Fit a curve of the form y = abx to the following data.

x1234
y41135100
5 marks

Answer

Sign in to view the complete answer paper.

4

Solve the following system of equations using L-U decomposition method.

2x + 3y + z = 9; x + 2y + 3z = 6; 3x + y + 2z = 8
10 marks

Answer

Sign in to view the complete answer paper.

OR
510 marks
a

Find dy/dx at x = 0.1 from the following table.

x0.00.20.40.60.81.0
y0.00.120.481.102.03.20
5 marks

Answer

Sign in to view the complete answer paper.

b

Find an approximate value of y(0.1) for dy/dx = (y-x)/(y+x), y(0)=1 by Euler’s method with h = 0.02.

5 marks

Answer

Sign in to view the complete answer paper.

610 marks
a

Obtain the Fourier series for f(x) = x2 in [-π, π] and hence show that 1/12 - 1/22 + 1/32 - 1/42 + ... = π2/12.

5 marks

Answer

Sign in to view the complete answer paper.

b

Find the half range cosine series for the function f(x) = x in [0, π].

5 marks

Answer

Sign in to view the complete answer paper.

OR
7

Find the Fourier transform of f(x) = 1-x2 for |x|<1, and 0 for |x|>1, and hence evaluate: ∫0∞ ((x cos x - sin x)/x3) cos(x/2) dx.

10 marks

Answer

Sign in to view the complete answer paper.

810 marks
a

Solve p + q = z tan(x + 2y) + 5.

5 marks

Answer

Sign in to view the complete answer paper.

b

Solve z = px + qy + p2 + q2 by Charpit’s method.

5 marks

Answer

Sign in to view the complete answer paper.

OR
9

A square plate is bounded by the lines x=0, y=0, x=20 and y=20 and its Faces are insulated. The temperature along the upper horizontal edge is given by u(x,20) = x(20-x), 0 < x < 20 while other three edges are kept at 0°C. Find the steady state temperature in the plate.

10 marks

Answer

Sign in to view the complete answer paper.

1010 marks
a

Find the directional derivative of f(x,y,z) = x2y2z + 4xz at (1, -2, 1) in the direction of the vector 2i - j - 2k.

5 marks

Answer

Sign in to view the complete answer paper.

b

If F = grad(x3+y3+z3-3xyz), find div F and curl F.

5 marks

Answer

Sign in to view the complete answer paper.

OR
11

Verify Green’s theorem for ∫c [(x-y)dx + (x+y)dy], where C is the rectangle with vertices (0,0), (π,0), (π,1) and (0,1).

10 marks

Answer

Sign in to view the complete answer paper.

About this paper

This page contains the question paper of MATHEMATICAL METHODS from JNTU for B.Tech ECE I Year I-I, August - 2018, R15.

For the solved question paper with answers, switch to the Answer Paper tab.

Other papers in MATHEMATICAL METHODS

Loading Question Papers

Fetching data from database...