BT-401 (GS) – Mathematics-III

B.Tech., IV Semester
Examination, November 2023
Grading System (GS)
Max Marks: 70 | Time: 3 Hours

Note:
i) Attempt any five questions.
ii) All questions carry equal marks.

Previous Year Questions (November 2023)

Q.1

a) Evaluate $\sqrt{12}$ to four decimal places by Newton Raphson Method. (Unit 1)


b) What is the rate of convergence of bisection method? (Unit 1)


Q.2

a) Prove that
i) $\Delta = \frac{1}{2} \delta^2 + \delta \sqrt{1 + \left(\frac{\delta^2}{4}\right)}$
ii) $\Delta + \nabla = \frac{\Delta}{\nabla} - \frac{\nabla}{\Delta}$ (Unit 1)


b) Construct a backward difference table for $y = \log x$ given that

$x$1020304050
$y$11.30101.47711.60211.6990

And find values of $\nabla^3 \log 40$ and $\nabla^4 \log 50$ (Unit 1)


Q.3

a) Using following table, by Lagrange's Method find $f(x)$ as a polynomial in $x$:

$x$-10367
$f(x)$3-6398221611

(Unit 1)


b) Using Newton's divided difference formula, calculate the value of $f(6)$ from the following data:

$x$1278
$f(x)$1554

(Unit 1)


Q.4

a) Find $f'(1.1)$ and $f''(1.1)$ from the following table:

$x$1.01.21.41.61.82.0
$f(x)$0.00.12800.55401.29602.43204.0

(Unit 2)


b) Find missing values in the following table:

$x$0510152025
$y$610-17-31

(Unit 1)


Q.5

a) Find $\int_0^6 \frac{e^x}{1+x} dx$ approximately using simpson's $\frac{3}{8}$th rule on integration. (Unit 2)


b) Solve the equation $\frac{dy}{dx} = 1 - y$ with initial condition $y(0) = 0$ using Euler's modified method and tabulate the solution at $x = 0.1, 0.2, 0.3$. (Unit 3)


Q.6

a) Using Lagrange's interpolation formula to fit a polynomial to the data:

$x$-1023
$f(x)$-83112

(Unit 1)


b) Using Regula-Falsi method, find the real root of $x \log_{10} x = 1.2$, correct to four decimal places. (Unit 1)


Q.7

a) Solve $\frac{dy}{dx} = x + y^2$ by using Runge-Kutta method of fourth order to find an approximate value of $y$ for $x = 0.2$, given that $y = 1$ when $x = 0$. (Take $h = 0.1$) (Unit 3)


b) Evaluate $L^{-1} \left[ \frac{s+7}{s^2 + 4s + 8} \right]$ (Unit 4)


Q.8

a) Find the inverse Laplace transform of $\frac{s+4}{s(s-1)(s^2+4)}$. (Unit 4)


b) Prove that if $L\{f(t)\} = F(s)$ then $L \left\{ \frac{1}{t} f(t) \right\} = \int_s^\infty F(s) ds$ hence, evaluate $\frac{e^{at} - \cos bt}{t}$. (Unit 4)