Finding the Chebyshev polynomials
Question 1.
- Using the formula Tn(x) = cos(n cos−1 x), n ≥ 0, find the Chebyshev polynomials T0(x), T1(x), T2(x), T3(x), and T4(x). [8]
- Find the Chebyshev interpolating polynomial that attains the values 6, 1, 3, and 66 at the points −1, 0, 2 and 6. Reduce the polynomial to its natural form. [12]
Question 2.
- Find the Hermite interpolating polynomial for the function f(x) = √ x satisfying the conditions H5(xi) = √ xi , i = 0, 1, 2 and H 0 5 (xi) = 1/ 2 √ xi , i = 0, 1, 2 for the points x0 = 1, x1 = 4 and x2 = 9. Reduce the polynomial to its natural form. [15]
- Find the error bound of the interpolating polynomial. [10]
Question 3.
The population of Botswana (in millions) for the years 1970 to 2020 is given in the table.
Year 1970 1980 1990 2000 2010 2020
Population, P 0.628 0.898 1.287 1.643 1.987 2.254
- Make a scatter plot (population versus years) for the data. [3]
- Using the scatter plot determine the data trend and law of the curve of best fit for the data. [3]
- Use the least squares method find the curve of best fit for the data. [11]
- Hence estimate the population of Botswana in the year 2036. [3]
Question 4.
Fit the curve y = a (1 − bx) 2 to the data x 4 6 8 10 11 12 y 4.89 5.49 6.62 9 11.4 16.1 [11]
Question 5.
Evaluate the integral I = Z 3 1 1 x d x using the trapezoidal rule method with accuracy ε
