There are infinitely many polynomials of order 2 (quadratics) that will give these as the first two numbers and any one of these could be "the" rule. Short of reading the mind of the person who posed the question, there is no way of determining which of the infinitely many solutions is the "correct" one.It is not even possible to tell whether the sequence is arithmetic (additive) or geometric (multiplicative). There is simply not enough information.Any one of -n^2 + 10n - 21, -0.5n^2 + 8.5n - 20, 7n - 19, 0.5n^2 + 5.5n - 18, will do.
There is no pattern
Clearly, if you omit the sign, the nth. term will be 4n. The alternating sign can easily be expressed as a power of (-1), so in summary, the nth. term is (-1)n4n.
tn=5n-3
If you mean 3, 6, 9, 12 then the nth term is 3n
t(n) = t(n - 1) + (10n - 9)
12 - 5(n-1)
The nth term of the sequence is expressed by the formula 8n - 4.
The nth term is 5n-3 and so the next term will be 22
Given n and any number for the nth term, it is a simple matter to find a rule such that the above four numbers are the first four of a sequence and the given number in the nth position.However, the simple answer for simple questions is Un = 4n
nth term is n squared plus three
Here are the first five terms of a sequence. 12 19 26 33 40 Find an expression for the nth term of this sequence.
5
24 - 6n
There is no pattern
The sequence has a difference of 10, so the nth term starts with 10n. Then to get to -8 from 10 you need to subtract 18. So the nth term is 10n - 18.
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, ...
The nth term of the sequence -4 4 12 20 29 is 8n+12 because each time the sequence is adding 8 which is where the 8n comes from. Then you take 8 away from -4 and because a - and - equal a + the answer is 12. Which is where the 12 comes from. Hope I helped.