Question

Given the functions f(n) = 11 and g(n) = -2(n - 1), combine them to create an arithmetic sequence, an, and solve for the 31st term.

   an = 11 - 2(n - 1); a31 = -49
   an = 11 - 2(n - 1); a31 = -51
   an = 11 + 2(n - 1); a31 = 71
   an = 11 + 2(n - 1); a31 = 73

Answer 1

an = 11 - 2(n - 1); a31 = -49 

Answer 2

Answer:

Option A is correct

$a_n = 11-2(n-1)$ and  $a_{31} = -49$

Step-by-step explanation:

Given the functions:

$f(n) = 11$

$g(n) = -2(n-1)$

then;

combine them to create an arithmetic sequence i.e,

$a_n = f(n)+g(n)$

⇒$a_n = 11-2(n-1)$ where n is the number of terms

To find the 31st term.

Substitute n =31 we have;

$a_n = 11-2(31-1)$

⇒$a_{31}=11-60 = -49$

Therefore, we have an arithmetic sequence,

$a_n = 11-2(n-1)$ and  $a_{31} = -49$