Kablow!

Sequences

플레이하며 배우기

이 문제들을 풀어 에너지를 얻은 뒤 낚시하고 탐험하세요. 계정이 필요 없어요.

교육자를 위해: Sequences(Mathematics, Algebra)을(를) 위한 바로 쓸 수 있는 수업 슬라이드, 복습 노트 — 수업에 사용하거나, 학습자들이 실시간 게임으로 즐기는 인터랙티브 클래스 활동으로 진행하세요.

수업 노트

Terms and rules

  • A sequence is a list of numbers that follows a rule. Each number is a term; un or T(n) is the nth term.
  • A term-to-term rule says how to get from one term to the next (e.g. add 4). A position-to-term rule (the nth term) gives any term directly.
  • Here positions are positive integers starting at n = 1.

Arithmetic sequences

  • An arithmetic (linear) sequence goes up or down by a constant common difference d.
  • The nth term is dn + (a - d), where a is the first term. For 5, 8, 11, 14: d = 3, so 3n + 2.
  • To check whether a number is in the sequence, solve 3n + 2 = \text{number} and see if n is a positive integer.

Geometric sequences

  • A geometric sequence multiplies by a constant common ratio r: 3, 6, 12, 24 has r = 2. The nth term is arn-1.
  • Fibonacci-type sequences add the previous two terms.

Quadratic sequences

  • A constant nonzero second difference identifies a quadratic sequence an² + bn + c, with a equal to half that difference. Zero second difference gives a linear or constant sequence.
  • For 2, 7, 14, 23: first differences 5, 7, 9; second difference 2, so a = 1. Subtract n2 (1, 4, 9, 16) to leave 1, 3, 5, 7 = 2n - 1. So n2 + 2n - 1.

Differences in a quadratic sequence

Differences in a quadratic sequencenuₙFirst difference12—2753147423953411

Special sequences

  • Square numbers 1, 4, 9, 16; cube numbers 1, 8, 27, 64; triangular numbers 1, 3, 6, 10; powers of 2: 2, 4, 8, 16.

슬라이드

Sign up free to view the lesson slides

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

연습 문제

무료 미리 보기 — 34개 중 8개 문제. 가입하면 전부 볼 수 있어요.
  1. 1.What do we call each number in a sequence?

    Easy
    • Aa term
    • Ba factor
    • Ca power
    • Da root
  2. 2.What is the next term of 2, 5, 8, 11?

    Easy
    • A13
    • B14
    • C15
    • D12
  3. 3.What is the common difference of 10, 7, 4, 1?

    Easy
    • A3
    • B-3
    • C7
    • D-7
  4. 4.What is the next term of 3, 6, 12, 24?

    Easy
    • A30
    • B36
    • C48
    • D72
  5. 5.What is the nth term of 5, 8, 11, 14?

    Easy
    • A3n + 2
    • B3n + 5
    • Cn + 3
    • D5n
  6. 6.What is the nth term of 10, 20, 30, 40?

    Easy
    • An + 10
    • B10n
    • C10n + 10
    • Dn10
  7. 7.What is the 10th term of 2n + 5?

    Easy
    • A20
    • B25
    • C15
    • D30
  8. 8.What is the nth term of 20, 17, 14, 11?

    Easy
    • A23 - 3n
    • B3n + 17
    • C20 - 3n
    • D3n - 23

Unlock all 34 questions & more

무료 계정을 만들어 이 주제의 모든 문제, 슬라이드, 플래시카드, 복습 노트를 확인하세요.

기출 문제

이 주제의 기출 문제 연습이 곧 나와요.
곧 출시