# Recursive & Explicit Formulas

## Presentation on theme: "Recursive & Explicit Formulas"— Presentation transcript:

Recursive & Explicit Formulas
January 5 – 7, 2010

Closed/Explicit Formula
January 6, 2010 Closed/Explicit Formula

Warm Up (1/6) You can burn 5 calories a minute from walking. Which set could represent the range of calories burned when walking between 1 and 5 minutes? a. {1,2,3,4,5} c. {5} b. {5,10,15,20,25} d. {1,5} Which sequence is not a linear function? a. 1,2,3… c. 2,5,8… b. 1,4,9 d. -12,-8,-4… Given the first term in the sequence below, use the recursive formula given to find the next four terms of the sequence. a. 15,12,9,6 c. -3,6,12,18 b. 18,15,12,9 d. 18,12,6,-3

Explicit Formula for the nth term of a sequence
nth term 1st term # of common the term difference trying to find Find the indicated term.

What is the 23rd term of the following sequence?
5, 12, 19, 26, … a1 = 5; d = 7

You Try! Find the 9th term in the following sequence: 9, 2, -5, -12,…
a1 = 9; d = -7

Practice 13, 25, 37, 49,… find the 25th term a1 = 13; d = 12

Write the equation for the nth term
17, 28, 39, 50, … a1 = 17; d = 11 7, 4, 1, -2, … a1 = 7; d = -3

Sequence 1: -4, 1, 6, 11, … Find common difference (d)
Write the sequence in explicit /closed form: tn = t1 + (n-1)d tn = (n-1)(5) Find the 10th term --- Find the 25th term ---

Sequence 2: 8, 5, 2, -1, … Find common difference (d)
Write the sequence in explicit/closed form: tn = t1 + (n-1)d tn = 8 + (n-1)(-3) Find the 10th term --- Find the 25th term ---

Sequence 3: -2, -4, -6, -8, … Find common difference (d)
Write the sequence in explicit/closed form: tn = t1 + (n-1)d tn = (n-1)(-2) Find the 10th term --- Find the 25th term ---

Sequence 4: 4, 7, 10, 13, … Find common difference (d)
Write the sequence in explicit/closed form: tn = t1 + (n-1)d tn = 4 + (n-1)(13) Find the 10th term --- Find the 25th term ---

Homework Textbook p. 145; and 45 ALL