Page 22 - 新思维数学学生用书6 样章

2.1 Counting and sequences

Continued

b What is the position-to-term rule for the sequence?

c Imagine the sequence continues forever.
What is the 50th term in the sequence?

a 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 Follow the instructions in the flow diagram.
We include 20 because it is not ‘more than 20’.

b Position Term Make a table to show the position and the term.
1 2 Look at how the position number is connected
2 4 to the term number.

3 6

Multiply by 2

The position-to-term rule is: Use the position-to-term rule to find the 50th term.
multiply by 2.

c 50 × 2 = 100

Exercise 2.1

1 a Find the position-to-term rule for the numbers in this table.

Position Term
1 6
2 12

3 18
4 24
10

b What is the 10th term of the sequence 6, 12, 18, …?

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