Question

What is the 32nd term of the arithmetic sequence where a1 = -33 and a9 = -121? thanks



-396
-385
-374
-363

Answer 1

im not really sure?

Answer 2

well i got 385? but im not sure

Answer 3

ya

Answer 4

Generate a general formula for the \(n\)th term, and then evaluate. Hint: You know it's an arithmetic sequence, so your formula should be linear.\[a_n=\ ?\]

Answer 5

I believe the question is correct. an arithmetic sequence is formed as follows:

a, a+d, a+2d, a+3d, ...

where 'a' is the first term (which can be written as 1st term)

Answer 6

similarly 32nd term means the thirty-second term in the sequence

Answer 7

i.e. term number 32

Answer 8

a1 is first term
a9 is 9'th term

Answer 9

it usually written as:\[a_1,a_2,a_3,...,a_9,...,a_{32},...,a_n\]

Answer 10

the general formula for the n'th term is:\[a_n=a_1+(n-1)d\]where \(a_1\) is the first term and \(d\) is the common difference between each term.

Answer 11

so, using this, we get the 9'th term as:\[a_9=a_1+(9-1)d=a_1+8d\]and you are given:\[a_1=-33\text{ and }a_9=-121\]so use this to solve the question.