CSC212 · TU past paper
Numerical Method 2078 question paper
The complete TU 2078 exam paper for Numerical Method (CSC212), all 12 questions with solved model answers written to the mark scheme.
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- 110 marksNumericalHorner's methodHideAnswer
How can Horner’s rule be used to evaluate the f(x) and f(x) of a polynomial at a given point? Explain. Write an algorithm and program to calculate a real root of a polynomial using Horner’s rule.[10]
Horner's rule is an efficient scheme for evaluating a polynomial and its derivative at a point by rewriting the polynomial in nested form. It is closely related to synthetic division and the Remainder Theorem. For a polynomial of degree ...
- 210 marksNumericalMatrix factorization and Solving System ofHideAnswer
Matrix Factorization and Solving Linear Systems
Matrix factorization expresses a square matrix $A$ as a product of two triangular matrices: $$A = LU$$ where $L$ is lower triangular (with unit diagonal in Doolittle's method) and $U$ is upper triangular. This is called LU decomposition....
- 310 marksNumericalSolution of the higher order equationsHideAnswer
Higher-Order Differential Equations
A higher-order differential equation is a differential equation in which the highest derivative of the dependent variable is of order two or more. The given equation $$\frac{d^2y}{dx^2} + 3\frac{dy}{dx} + 5y = 0$$ is a second-order ODE (...
- 45 marksNumericalHalf-Interval method and ConvergenceHideAnswer
How the half-interval method can be estimate a root of a non-linear equation? Find a real root of the following equation using the half-interval method to correct up to two decimal places. $x^2 - e^{-x} - x = 1$ [5]
- Equation: $x^2 - e^{-x} - x = 1$ - Rearranged: $f(x) = x^2 - e^{-x} - x - 1 = 0$ - Required accuracy: two decimal places The half-interval (bisection) method is based on the Intermediate Value Theorem: if $f(x)$ is continuous on
- 55 marksNumericalFixed point iteration and its convergenceHideAnswer
Calculate the real root of the given equation using fixed point iteration correct up to 3 significant figures. $2x^3 - 2x = 5$. [5]
- Equation: $2x^3 - 2x = 5$, i.e. $f(x) = 2x^3 - 2x - 5 = 0$ - Method: Fixed point iteration - Required accuracy: 3 significant figures No initial guess given; must be determined by root location. Rearrange to $x = g(x)$: $$2x^3 = 5 + 2x...
- 65 marksNumericalNewton's Interpolation using divided diffeHideAnswer
Newton's Interpolation
What is Newton's interpolation? Obtain the divided difference table from the following data set and estimate the f(x) at x = 2 and x = 5.
$$\begin{array}{c|ccccc} x & 3.2 & 2.7 & 1.0 & 4.8 & 5.6 \ \hline f(x) & 22.0 & 17.8 & 14.2 & 38.3 & 51.7 \end{array}$$
[5]
- 75 marksNumericalLinear RegressionHideAnswer
Linear Regression Question
What is linear regression? Fit the linear function to the following data.
$$\begin{array}{c|cccccccc} x & 1.0 & 1.2 & 1.4 & 1.6 & 1.8 & 2.0 & 2.2 & 2.4 \ \hline f(x) & 2.0 & 2.6 & 3.9 & 6.0 & 9.3 & 15.0 & 20.6 & 30.4 \end{array}$$
[5]
Linear regression is a curve-fitting technique that determines the best-fit straight line through a set of data points using the least squares principle, which minimizes the sum of squares of the residuals (vertical deviations) between o...
- 85 marksCubic spline interpolationHideAnswer
What are the problems with polynomial interpolation for a large number of data set? How such problems are addressed? Explain with an example. [5]
When the number of data points is large, a single polynomial of degree n-1 must be fitted through all n points. This approach suffers from several serious problems: For a large number of data points, a high-degree interpolating polynomia...
- 95 marksNumericalRomberg integrationHideAnswer
Evaluate the following integration using Romberg integration. $$\int_{0}^{1} \frac{\sin^2 x}{x} dx$$ [5]
- Integrand: $f(x) = \dfrac{\sin^2 x}{x}$ - Limits: $a = 0$, $b = 1$ - Interval length: $b - a = 1$ Removable singularity at $x=0$: $\lim{x\to 0}\frac{\sin^2 x}{x} = \lim{x\to0}\frac{x^2}{x} = 0$, so $f(0)=0$. $x$ $\sin x$ $\sin^2 x$
- 105 marksNumericalGauss-Jordan methodHideAnswer
Solve the following set of linear equations using the Gauss-Jordan method.
$$x_2 + 2x_3 + 3x_4 = 9$$ $$7x_1 + 6x_2 + 5x_3 + 4x_4 = 33$$ $$8x_1 + 9x_2 + x_4 = 27$$ $$2x_1 + 5x_2 + 4x_3 + 3x_4 = 23$$
[5]
$$ \begin{aligned} x2 + 2x3 + 3x4 &= 9 \quad (1)\ 7x1 + 6x2 + 5x3 + 4x4 &= 33 \quad (2)\ 8x1 + 9x2 + 0x3 + x4 &= 27 \quad (3)\ 2x1 + 5x2 + 4x3 + 3x4 &= 23 \quad (4) \end{aligned} $$ $$ \left[\begin{array}{ccccc} 0 & 1 & 2 & 3 & 9 \ 7...
- 115 marksNumericalHeun's methodHideAnswer
Solve the following differential equation for $1 \leq x \leq 2$, taking $h = 0.25$ using Heun’s method. $y'(x) + x^2y = 3x$, with $y(1) = 1$. [5]
- ODE: $y'(x) + x^2 y = 3x$, so $y'(x) = 3x - x^2 y = f(x,y)$ - Initial condition: $y(1) = 1$ - Step size: $h = 0.25$ - Interval: $1 \le x \le 2$ - Number of steps: $(2-1)/0.25 = 4$ $$y{i+1} = yi + \frac{h}{2}(m1 + m2)$$ where
- 125 marksNumericalLaplacian equation and Poisson's equationHideAnswer
Consider a metallic plate of size 90cm by 90cm. The two adjacent sides of the plate are maintained at a temperature of $100^\circ C$ and the remaining two adjacent sides are held at $200^\circ C$. Calculate the steady-state temperature at interior points assuming a grid size of 30 cm by 30 cm. [5]
- Plate: 90 cm × 90 cm - Grid spacing: $h = 30$ cm → interior nodes form a 2×2 arrangement (4 unknowns) - Two adjacent sides at $100^\circ C$ - Remaining two adjacent sides at $200^\circ C$ Governing equation: $$\frac{\partial^2 T}{\part...