MATH 152, Fall 2013 Week In Review Week 9 1. Determine if the following sequence is convergent ln(2 + en ) . 3n 2. Determine if the following sequence is convergent (−3)n . n! 3. Determine if the following sequence is convergent n3 . n! 4. Determine if the following sequence is convergent 1·3·5· 1 5. Determine if the following sequence a1 = 1 an+1 = 1 + an limit. 6. The Fibonacci sequence is dened by f1 = 1, show an−1 = 1 + 1 an−2 f2 = 1, · · · · (2n − 1) . (2n)n f or n≥1 fn = fn−1 + fn−2 . Assuming that an is convergent,nd its limit is convergent. If so, the nd its f or n ≥ 3. Let an = fn+1 and fn 1 7. Show that the sequence a1 = 2 an+1 = f or n ≥ 1, satises 0 < an ≤ 2 and is decreasing. Deduce 3 − an that the sequence is convergent, and nd its limits. 1 f or n ≥ 1. Find the rst eight terms of the 8. A sequence is dened recursively by a1 = 1 an+1 = 1 + 1 + an sequence. What do you notice about the odd terms and even terms ? By cinsidering the odd and even terms separately, show that an is convergent and nd its limit . ∞ X 1 1 √ −√ . 9. Determine the sum of the series n n+1 n=1 10. Let an = ∞ X 2n . Determine whether {an } is convergent. Determine whether an is convergent. 3n + 1 n=1 11. Determine whether the series 4 + 32 8 16 + + + · · · is convergent or divergent. If it is convergent, nd its sum. 5 25 125 ∞ X 1 12. Determine whether the series is convergent or divergent. If it is convergent, nd its sum. e2n n=1 13. Determine whether the series ∞ X [2(0.1)n + (0.2)n ] is convergent or divergent. If it is convergent, nd its sum. n=1 14. Determine whether the series 15. Determine whether the series ∞ X n2 is convergent or divergent. If it is convergent, nd its sum. 3(n + 1)(n + 2) n=1 ∞ X 1 is convergent or divergent. If it is convergent, nd its sum. n(n + 2) n=1 16. Determine whether the series 17. Determine whether the series ∞ X 1 is convergent or divergent. If it is convergent, nd its sum. 2−1 4n n=1 ∞ X n=1 18. Determine whether the series ∞ X √ n is convergent or divergent. If it is convergent, nd its sum. 1 + n2 1 is convergent or divergent. If it is convergent, nd its sum. 1 + 2−n n=1 19. Find the values for x such that the series ∞ X (x − 3)n is convergent. Find the sum for those values of x. n=1 20. Find the values for x such that the series 21. Find the values for x such that the series ∞ X 1 is convergent. Find the sum for those values of x. n x n=1 ∞ X n=1 tann x is convergent. Find the sum for those values of x. ∞ X 22. Find the sum of the series 1 . (4n − 1)(4n − 3) n=1 23. Find the sum of the series ∞ X n2 + 3n + 1 . (n2 + n)2 n=1 24. If the n − th partial sum of a series ∞ X an is n=1 sn = nd an and ∞ X n=1 an . n−1 n+1 25. If the n − th partial sum of a series ∞ X an is n=1 sn = 3 − n2−n nd an and ∞ X an . n=1 26. What is the value for c if ∞ X (1 + c)−n . n=1 27. Suppose that ∞ X n=1 an an 6= 0, is known to be convergent. Prove that ∞ X 1 is divergent. a n=1 n 28. Write out the partial fraction decomposition of the function values of the coecients. 29. Write out the partial fraction decomposition of the function numerical values of the coecients. x4 + x2 + 1 . Do not determine the numerical + 1)(x2 + 4)2 (x2 (x − 19x . Do not determine the + 5x + 3)2 1)3 (4x2 x3 + x2 + 1 30. Write out the partial fraction decomposition of the function 4 . Do not determine the numerical x + x3 + 2x2 values of the coecients. 18 − 2x − 4x2 dx . + 4x2 + x − 6 31. Evaluate the integral Z 32. Evaluate the integral Z x4 dx . x4 − 1 33. Evaluate the integral Z x3 − 2x2 + x + 1 dx . x4 + 5x2 + 4 x3 34. Evaluate the integral Z 4 1 dx . x2 + x − 6 2 1 dx . x2 − 1 0 35. Evaluate the integral Z 36. Evaluate the integral Z −2 0 ∞ √ 1 dx . x(1 + x) 37. If the innite curve y = e−x , x ≥ 0, is rotated about the x − axis, nd the area of the resulting surface. 38. Find the area of the surface obtained by rotating the curve x = acos3 (θ), y = asin3 (θ), x − axis. 0 ≤ θ ≤ π/2 about the 39. Set up the integral giving the surface area of the ellipsoid obtained by rotating the ellipse x = acos(θ), y = bsin(θ), a ≥ b, about the y − axis.