S6 Ch.20 等差數列 Arithmetic Sequence Intro

Ch.20 數列 Sequence

7 Sept 2020_FYK

Multiple Select

Which of the following is/are Arithmetic Sequence?

以下哪些數列是等差數列?

• 1,5,9

• 2,10,16

• 4,12,20

• 5,10,20

Arithmetic Sequence 等差數列

• have a common difference 有公差

• d= 後項- 前項

• 1,5,9                  d=4

• 4,12,20             d=8

  
  
  No common d:

• 2,10,16

• 5,10,20

Multiple Select

Which of the following is/are Arithmetic Sequence?

以下哪些數列是等差數列?

• 100, 50, 0, -50

• 5, 10,15, 20

• 9,19,29,39

• 2,22,222,2222

Arithmetic Sequence 等差數列

• have a common difference 有公差

• d= 後項- 前項

• 100, 50, 0, -50                 d=-50

• 5, 10,15, 20                     d=5

• 9,19,29,39                      d= 10

• 2,22,222,2222                no common d
  
  

Multiple Choice

Is it arithmetic sequence? 以下是等差數列嗎?

37, 31, 25, 19, ...

• Yes

• No

Multiple Choice

Is it arithmetic sequence?

以下是等差數列嗎?

78, 785, 7855, 78555, ...

• Yes

• No

Multiple Choice

Find the missing term of the arithmetic sequence.

在等差數列中,求橫線的數值。

98, __, 66

• 82

• 77

• 80

• I don't know

Multiple Choice

Find the common difference:

求公差:

-34, -29, -24, -19, ...

• d=6

• d=5

• d=-5

• d=-6

Multiple Choice

Find the common difference:

求公差:

29, 21, 13, 5, ...

• d=7

• d=8

• d=-8

• d=-7

Multiple Choice

Find the common difference:

求公差:

-18, -23, -28, -33, ...

• d=5

• d=4

• d=-4

• d=-5

Conclusion 總結

AS has common difference which can be found easily by the latter minus the number before.
等差數列有公差, 後項-前項