Respuesta :

Answer:

a) [tex]a_n=3n-1[/tex]

b) [tex]a_n=2n+7[/tex]

Step-by-step explanation:

a)  From inspection, we can see that this is an arithmetic sequence as the difference between each term is the same:

14 - 11 = 3

11 - 8 = 3

8 - 5 = 3

5 - 2 = 3

(so the common difference = 3)

General equation of arithmetic sequence:  [tex]a_n=a+(n-1)d[/tex]

(where [tex]a[/tex] is the first term and [tex]d[/tex] is the common difference between terms)

Given:

  • [tex]a=2[/tex]
  • [tex]d=3[/tex]

[tex]\implies a_n=2+(n-1)3[/tex]

[tex]\implies a_n=2+3n-3[/tex]

[tex]\implies a_n=3n-1[/tex]

b)  From inspection, we can see that this is an arithmetic sequence as the difference between each term is the same:

17 - 15 = 2

15 - 13 = 2

13 - 11 = 2

11 - 9 = 2

(so the common difference = 2)

General equation of arithmetic sequence:  [tex]a_n=a+(n-1)d[/tex]

(where [tex]a[/tex] is the first term and [tex]d[/tex] is the common difference between terms)

Given:

  • [tex]a=9[/tex]
  • [tex]d=2[/tex]

[tex]\implies a_n=9+(n-1)2[/tex]

[tex]\implies a_n=9+2n-2[/tex]

[tex]\implies a_n=2n+7[/tex]