Find the 99th term of the arithmetic sequence 2, -3, -8,
Mathematics · High School · Thu Feb 04 2021
Answered on
Given the sequence:
2, -3, -8
Determine the 99th term of the arithmetic sequence.
Formula for Arithmetic Sequence:
An = A1 + ( n - 1 ) d
A1 = 2
A2 = -3
n = 99
Solution:
In order to determine the 99th term, we simply need to find the common difference or d. To do so, we subtract the 2nd term by the 1st term.
Common Difference = 2nd Term - 1st Term
Common Difference = -3 - 2
Common Difference = -5
A99 = 2 + ( 99 - 1 ) -5
A99 = 2 + ( 98) - 5
A99 = 2 - 490
A99 = -398
Final answer:
A99 = -398