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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

User Shavareppa
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2 Answers

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an = 11 - 2(n - 1); a31 = -49
User Corydoras
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5 votes

Answer:

Option A is correct


a_n = 11-2(n-1) and
a_(31) = -49

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

User Sherin Jose
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