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.
(A) an = 11 - 2(n - 1); a31 = -49
(B) an = 11 - 2(n - 1); a31 = -51
(C) an = 11 + 2(n - 1); a31 = 71
(D) an = 11 + 2(n - 1); a31 = 73

Answer 1

first what will you get for each function when you plug in 31 for n?

Answer 2

the 1st part, combining the functions means to add them

f(n) + g(n) =

for the 2nd part, using the combined function, substitute n = 31 and solve

Answer 3

I got (C) as my answer.

Answer 4

I think you need to go and check the substitution... and the order of operation

\[a_{31} = 11 - 2(31 -1)\]

Answer 5

A ??!! @campbell_st