It is -148.
10-2x for x = 0, 1, 2, 3, ... Since the domain of an arithmetic sequence is the set of natural numbers, then the formula for the nth term of the given sequence with the first term 10 and the common difference -2 is an = a1 + (n -1)(-2) = 10 - 2n + 2 = 12 - 2n.
It is 60.
An arithmetic sequence is where a constant is added to the base case, and then added again until the proscribed limit is reached. An example is 1, 3, 5, 7, where the constant is 2 and the base case is 1. The constant can be negative, such as -4, base case 16, which leads to a descending sequence of 16 12 8 4 0 -4 -8...
It is: -3072
The sequence 216 12 23 is neither arithmetic nor geometric.
8 + 4n
18 - 6n
The sequence in the question is NOT an arithmetic sequence. In an arithmetic sequence the difference between each term and its predecessor (the term immediately before) is a constant - including the sign. It is not enough for the difference between two successive terms (in any order) to remain constant. In the above sequence, the difference is -7 for the first two intervals and then changes to +7.
If a11 = 12 then a43 = a11 + 32*d = 12 + 32*(-6) = -180.
An arithmetic sequence in one in which consecutive terms differ by a fixed amount,or equivalently, the next term can found by adding a fixed amount to the previous term. Example of an arithmetic sequence: 2 7 12 17 22 ... Here the the fixed amount is 5. I suppose any other type of sequence could be called non arithmetic, but I have not heard that expression before. Another useful kind of sequence is called geometric which is analogous to arithmetic, but multiplication is used instead of addition, i.e. to get the next term, multiply the previous term by some fixed amount. Example: 2 6 18 54 162 ... Here the muliplier is 3.
Give the simple formula for the nth term of the following arithmetic sequence. Your answer will be of the form an + b.12, 16, 20, 24, 28, ...
It is neither.
12, 6, 0, -6, ...
The sum of the first 12 terms of an arithmetic sequence is: sum = (n/2)(2a + (n - 1)d) = (12/2)(2a + (12 - 1)d) = 6(2a + 11d) = 12a + 66d where a is the first term and d is the common difference.
The nth term is 3(n+1). The twenty-third term is equal to 3 x (23 + 1) = 72