Problem 1 [19 Marks]
1-1. Find the Pade approximation R2,2 (x) for f(x) = ln(l + x)/x starting with the MacLaurin expansion
f(x)
= 1-
x
-2
+
-x3 2
-
-x43 + -x54 -
··· .
[12]
1-2. Use the result m. 1-1. to establis. h ln(l + x)
fraction form.
R 3 '2
=
30x + 2lx 2 + x 3
30 + 36x + 9x2
and
express
R 3 '2
m•
continued
[7]
Problem 2 [30 Marks]
For any non negative interger n we define Chebyshev polynomial of the first kind as
Tn(x) = cos(n0), where 0 = arccos(x), for x E [-1, l].
2-1. Show the following property:
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Tn has n d1. stm. ct zeros xk E [-1, l]: xk = cos ((2k+2l)n1r)
for 0 :S k :Sn - l.
2-2. Compute the expressions of the first five Chebyshev polynomials of the first kind T0 , T1, T2 , T3 and
n.
2-3. Given the trucated power series f(x) = 1 + 2x - x3 + 3x4 .
(i) Economise the power series f(x).
[3]
(ii) Find the Chebyshev series for f(x).
[5]
;;:;-(i{) s_;:__wxx~h•~:~e~o~l:w~n:ftction f is even and use an apprnpriatecesult to find its Fouriecse;::;
2 , for 0 _<X < 7r.
2
(ii) Set x = 0 and conclude that ~ = 1 + }2 + ; 2 + ; 2 + · · ·.
[2]
Problem 3 [27 Marks]
3-1. Given the integral
3
(
Jo
slin+( 2xxs) dx
=
0.6717578646 · · ·
3-1-1. Compute T(J) = R(J, 0) for J = 0, l, 2, 3 using the sequential trapezoidal rule.
[10]
3-1-2. Use the results in 3-1-1. and Romberg's rule to compute the values for the sequential Simpson rule
{R(J, l)}, sequential Boole rule {R(J, 2)} and the third impprovement {R(J, 3)}. Display your results in
a tabular form.
[12]
3-2. State the three-point Gaussian Rule for a continuous function f on the interval [-1, l] and show that
the rule is exact for f (x) = 5x4 .
[5]
1