Math topic中文

Recurrence relation

Sequence generated by the relation un+1=f(un)u_{n+1} = \mathrm{f}(u_n), including the use of a graphing calculator or a computer to generate the sequence.

Practice questions

  1. 1已知数列{an}\{a_{n}\}中,a1=76a_{1}=\dfrac{7}{6},an2−an+1=an+1(n∈N∗)a_{n}^{2}-a_{n}+1=a_{n+1}(n\in N^{*}),SnS_{n}是{1an}\{\dfrac{1}{a_{n}}\}的前…
  2. 2A sequence is such that u0=2u_{0}=2 and un=un−1+n3+(12)nu_{n}=u_{n-1}+n^{3}+\left(\dfrac{1}{2}\right)^{n} for n≥1n\ge 1. (a) It is given…
  3. 3An arithmetic sequence has first term aa and common difference 0.50.5, where aa is an integer. Find the smallest value…
  4. 4Anand writes a computer programme to simulate a population of organisms in a controlled environment. It is assumed that…
  5. 5On the first day of last month, the temperature of a machine in a manufacturing plant was found to be 90∘C90^\circ\text{C}…
  6. 6Aenicillin, a type of bacteria, is grown in a petri dish. Its population doubles every six hours. Denoting the amount of…
  7. 7A sequence u1,u2,u3,…u_1, u_2, u_3, \dots is such that u1=12u_1 = \frac{1}{2} and un+1=un−n2+n−1(n+2)!,for all n≥1.u_{n+1} = u_n - \frac{n^2 + n - 1}{(n+2)!}, \quad \text{for all } n \ge 1.…
  8. 8A team of cyclists plans to ride from Singapore to Penang and back over 10 days. The distance for the route taken from S…
  9. 9A sequence of negative real numbers x1,x2,x3,…x_{1}, x_{2}, x_{3}, \dots satisfies the relation xn+1=−1−2xn, for n≥1.x_{n+1} = -\sqrt{1-2x_{n}}, \text{ for } n\ge 1.…
  10. 10Jane decides to purchase an apartment. To finance her apartment, she intends to apply for a bank housing loan of $847 5…
  11. 11A sequence u1,u2,u3,…u_1, u_2, u_3, \dots is such that un=2un−1−15n2+60n+Au_n = 2u_{n-1} - 15n^2 + 60n + A, where AA is a constant, and n≥2n \ge 2…
  12. 12Write 44r2+12r+5\dfrac{4}{4r^{2}+12r+5} in partial fractions. Find ∑r=2n44r2+12r+5\displaystyle\sum_{r=2}^{n} \dfrac{4}{4r^{2}+12r+5}. A sequ…
  13. 13A sequence u1,u2,u3,…u_1, u_2, u_3, \dots is such that u1=0u_1 = 0 and un+1=un+4+n−n2[(n+1)(n+2)]2, for all n∈Z+.u_{n+1} = u_n + \frac{4 + n - n^2}{[(n+1)(n+2)]^2}, \text{ for all } n \in \mathbb{Z}^+.…
  14. 14已知数列{an}\{a_{n}\}中,a1=1a_{1}=1,an⋅an+1=3na_{n}\boldsymbol{⋅}a_{n+1}=3^{n},n∈N∗n\in N^{*},则下列说法正确的是()(\quad) A. a4=9a_{4}=9 B…
  15. 15在数列{an}\left\{{a}_{n}\right\}中,a1=1a_{1}=1,an+1−an=7−2na_{n+1}-a_{n}=7-2n,则数列{an}\{a_{n}\}中最大项的数值为___.
  16. 16A sequence follows the recurrence relation Un+1−Un=2cos⁡((2n+1)x2)sin⁡x2U_{n+1}-U_n = 2\cos\left(\dfrac{(2n+1)x}{2}\right)\sin\dfrac{x}{2}, U1=sin⁡xU_1 = \sin x…
  17. 17已知正项数列{a}\{a\}满足nn--an=anan−(n⩾,n∈N+)an=anan-(n\geqslant ,n∈N+),aa. 设b=2n−1anb= \dfrac {2^{n-1}}{a_{n}},求列{bn}\{bn\}前项和TnTn.
  18. 18已知数列{an}\{a_{n}\}中,a1=1a_{1}=1,a2=2a_{2}=2,且an+1=4an−3an−1(n∈N∗,n⩾2)a_{n+1}=4a_{n}-3a_{n-1}(n∈N^{*},n\geqslant 2). ((Ⅰ))令bn=an+1−anb_{n}=a_{n+1}-a_{n}…
  19. 19Selena decides to borrow $200 000 from the bank to fund her home purchase on 1 January 2025. On the first day of each m…
  20. 20平面内有nn条直线,最多可将平面分成f(n)f(n)个区域,则f(n)f(n)的表达式为()(\quad) A. n+1          n+1\:\:\:\:\:\:\:\:\:\: B. 2n          2n\:\:\:\:\:\:\:\:\:\: …
  21. 21A sequence of real numbers x1,x2,x3,…x_1, x_2, x_3, \dots satisfies the recurrence relation xn+1=5xn+22xn+3 for all n≥1.x_{n+1} = \frac{5x_n + 2}{2x_n + 3} \text{ for all } n \ge 1.…
  22. 22已知数列{an}\left\{{{a}_{n}}\right\}对任意的n∈N∗n\in{{\mathbf{N}}^{*}},都有an∈N∗{{a}_{n}}\in{{\mathbf{N}}^{*}},且an+1={3an+1,an为奇数,an2,an为偶数. {{a}_{n+1}}=\left\{\begin{array}{l}3{{a}_{n}}+1,{{a}_{n}}\mathrm{为奇数},\\ \dfrac{{{a}_{n}}}{2},{{a}_{n}}\mathrm{为偶数}.\text{ }\\\end{array}\right.…
  23. 23A hospital patient is given a pill containing 50 units of antibiotic at 12pm. By 1pm, the number of units of antibiotic…
  24. 24A data processing centre processes data (in suitable units) every day. Let unu_n, where nn is an integer, n≥1n \ge 1, re…
  25. 25设数列{an}\{a_{n}\}满足an+1=4an−2an+1(n∈N∗)(1)a_{n+1}= \dfrac {4a_{n}-2}{a_{n}+1}(n∈N^{*})(1)若a1=3a_{1}=3,bn=2−anan−1(n∈N∗)b_{n}= \dfrac {2-a_{n}}{a_{n}-1}(n∈N^{*})…
  26. 26A sequence u1,u2,u3,…u_1,u_2,u_3,\dots is such that u1=34u_1 = \dfrac{3}{4} and un+1=un+34(12)2nu_{n+1} = u_n + \dfrac{3}{4}\left(\dfrac{1}{2}\right)^{2n}…
  27. 27A hospital patient is given a pill containing 50 units of antibiotic at 12pm. By 1pm, the number of units of antibiotic…
  28. 28Sarah, a Singaporean Citizen, started a 4-year undergraduate Computing course at the National University of Singapore (N…
  29. 29设数列{an}\{a_{n}\}满足a1=1a_{1}\text{=}1,a2=2a_{2}\text{=}2,an+2=(1+cos⁡2nπ2)an+sin⁡2nπ2{a}_{n+2}=(1+{{\rm\cos}}^{2}\dfrac{nπ}{2}){a}_{n}+{{\rm\sin}}^{2}\dfrac{nπ}{2}…
  30. 30A sequence u0, u1, u2, …u_0,\ u_1,\ u_2,\ \dots is such that u0=0u_0 = 0 and un=un−1−2−n(n2−4n+2),for all n∈Z+.u_n = u_{n-1} - 2^{-n}\left(n^2 - 4n + 2\right),\quad\text{for all } n \in \mathbb{Z}^+.…
  31. 31A sequence of negative real numbers x1,x2,x3,…x_1, x_2, x_3, \dots satisfies the relation xn+1=−1−2xn, for n≥1. x_{n+1} = -\sqrt{1-2x_n}, \text{ for } n \ge 1.…
  32. 32A sequence of positive numbers x1,x2,x3,…x_1, x_2, x_3, \dots satisfies the recurrence relation xn+1=10−3xn, for n=1,2,3,…x_{n+1} = \sqrt{10 - 3x_n} \text{, for } n = 1, 2, 3, \dots…
  33. 33At a particular bank, a savings account pays an interest of 0.9% per month on the last day of each month. On 1 January 2…
  34. 34On 1st Jan 2023, Mr Kim borrows $40000\char36{}40000 for his business from a bank. The bank provides two options for repaying the l…
  35. 35A sequence is such that u0=2u_0 = 2 and un=un−1+n3+(12)nu_n = u_{n-1} + n^3 + \left(\frac{1}{2}\right)^n for n≥1n \ge 1. It is given that…
  36. 36A sequence u1,u2,u3,…u_1, u_2, u_3, \dots is such that u1=13u_1 = \frac{1}{3} and ur+1=ur−1(2r−1)(2r+3),for all r≥1.u_{r+1} = u_r - \frac{1}{(2r-1)(2r+3)}, \quad \text{for all } r \ge 1.…
  37. 37A sequence u0,u1,u2,…u_0, u_1, u_2, \dots is such that u0=1u_0 = 1 and un=un−1+2n+1n(n+1),for all n∈N+.u_n = u_{n-1} + 2n + \frac{1}{n(n+1)}, \quad\text{for all } n \in \mathbb{N}^+.…
  38. 38Jeremy plans to invest $100 000 at the beginning of year 2024 into a current account which pays compound interest a…
  39. 39It is given that ∑r=1n2r(r+1)(r+2)=12−1(n+1)(n+2).\sum_{r=1}^n \dfrac{2}{r(r+1)(r+2)} = \dfrac{1}{2} - \dfrac{1}{(n+1)(n+2)}. State the sum to infini…
  40. 40已知数列{an}\{a_{n}\}满足an+an+1=2na_{n}+a_{n+1}=2n,SnS_{n}为其前nn项和,若a1=a4a_{1}=a_{4},则S101=()S_{101}=(\quad) A. 48824882 B. 51005100…
  41. 41Caleb is training for a vertical marathon, by running up the stairs of a building with 62 floors. He decides to train **…
  42. 42(1)三角形ABCABC中,AB=23,BC=2,∠C=600AB=2\sqrt{3},BC=2,\angle C={{60}^{0}},则三角形ABCABC的面积为___ (2)设等比数列{an}\left\{ {{a}_{n}} \right\}满足 a  ⁣1+a  ⁣3=10a{\,\!}_{1}+a{\,\!}_{3}=10…
  43. 43已知数列{an}\{a_{n}\}满足a1=1a_{1}=1,a2=13a_{2}= \dfrac {1}{3},若anan−1+2anan+1=3an−1an+1(n⩾2,n∈N+)a_{n}a_{n-1}+2a_{n}a_{n+1}=3a_{n-1}a_{n+1}(n\geqslant 2,n∈N^{+})…
  44. 44A sequence of negative real numbers x1,x2,x3,…x_1,x_2,x_3,\dots satisfies the relation xn+1=−1−2xn, for n≥1.x_{n+1} = -\sqrt{1-2x_n},\text{ for } n\ge 1.…
  45. 45A company posted a video on a social media platform to advertise a new product. The video is uploaded at the start of 1st1^{\text{st}}…
  46. 46A sequence of numbers, xnx_{n}, satisfy the relation xn+1=13(2xn+1xn2),n∈N+∪{0},0<x0<1.x_{n+1}=\tfrac{1}{3}\left(2x_{n}+\dfrac{1}{x_{n}^{2}}\right),\quad n\in\mathbb{N}^{+}\cup\{0\},\quad 0<x_{0}<1.…
  47. 47Caleb is training for a vertical marathon, by running up the stairs of a building with 62 floors. He decides to train th…
  48. 48A sequence u1,u2,u3,…u_1, u_2, u_3, \dots satisfies the recurrence relation un=n(n−1)2un−1u_n = \frac{n}{(n-1)^2}u_{n-1}, for n≥2n \ge 2. Giv…
  49. 49A sequence of real numbers x1,x2,x3,…x_{1}, x_{2}, x_{3}, \dots satisfies the recurrence relation xn+1=5xn+22xn+3for all n≥1.x_{n+1} = \dfrac{5x_{n} + 2}{2x_{n} + 3}\quad\text{for all } n \ge 1.…
  50. 50It is given that ∑r=1n2r(r+1)(r+2)=12−1(n+1)(n+2)\displaystyle \sum_{r=1}^n \frac{2}{r(r+1)(r+2)} = \frac{1}{2} - \frac{1}{(n+1)(n+2)}. State the sum…
  51. 51A first order recurrence relation for a sequence u0,u1,u2,…u_0, u_1, u_2, \dots is an equation that relates the general term unu_n…
  52. 52A first order recurrence relation for a sequence u0,u1,u2,…u_0, u_1, u_2, \dots is an equation that relates the general term unu_n…
  53. 53At the beginning of May 2016, Sam borrowed $50 000 from a bank that charges him a special rate of 0.2% interest at the…
  54. 54已知数列{an}\{a_{n}\}满足a1=1a_{1}\text{=}1,an+1=an2+3an(n∈N*)a_{n\text{+}1}\text{=}\dfrac{a_{n}}{2\text{+}3a_{n}}(n{\in}N^{\text{*}}),则下列结论…
  55. 55A radio game show called the Inverted Tower of Ionah is broadcasted live everyday. Each day, a participant is invited to…
  56. 56If u0=12u_0=\frac{1}{2} and un+1=3un2un+1u_{n+1}=\dfrac{3u_n}{2u_n+1} for any non-negative integer nn, write down the values of u1u_1…