Calculus
posted by Kelly on .
Write a formuls for the general term(nth term) of the arithmetic sequence. Do not use a recursion formula. Then use the formula for A to the n to find the indicated term of the sequence
find a11: 12, 10, 8,...

The first term is a1
Every subsequent term is a constant number d greater than the one before so it goes:
a1
a2 = a1 + d
a3 = a1 + 2d
a4 = a1 + 3d
a5 = a1 + 4d
.....
an = a1 + (n1)d
for example
a14 = a1 + 13*d 
makes no sense that's how i was doing it and I came up with 3.5
a11 = 12 + 10(.8444) = 3.5
however the answers to choose from are
.32
8
10
.34