[1011b] math 55 exercise 3

Page 1

Mathematics 55

2nd Semester 2010-2011

I.

1. Show that the sequence

n2 − ln n n3

converges by finding its limit.

2. What can be said about the convergence or divergence of the series

+∞ 2 X n − ln n ? n3 n=1

II. Find the sum of the series. 1.

+∞ n+1 X 2 n−1 3 n=1

2.

+∞ X

tan−1 n − tan−1 (n + 1)

n=1

III. Determine whether the given series converges or diverges. 1.

+∞ X sin n n2 + 1 n=1

4.

+∞ √ 3 X n−1 n=1

+∞ X

2.

(−1)n n2n en2 n=1

3.

+∞ X ln n n2 n=1

5.

n+1

+∞ X (−1)n−1 2n+1 (2n)! n=1

IV. Do as indicated. 1. Determine the radius and interval of convergence of the power series: (a)

+∞ X (−1)n xn−1 √ n+1 n=1

(b)

+∞ n X 3 (x + 1)n n n=1

2. Obtain a power series representation for: (a) f (x) =

x

(b) g(x) = ln |1 − 3x|

2

(2 + x2 )

3. Use the Maclaurin series for g(x) = cos x to evaluate the sum of the series 4. Give the third degree Taylor polynomial of f (x) =

√ 3

+∞ X (−1)n 9n . (2n)! n=0

x about -1 and use it to approximate

√ 3

−0.5.

dee.leyson All rights reserved.


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.