20th term = 20*(20+1)/2
It is 60.
1/6 n(n+1)(n+2)
You first have to figure out some rule for the sequence. This can be quite tricky.
i dont get it
The nth term is Un = a + (n-1)*d where a = U1 is the first term, and d is the common difference.
46
It is 60.
First, you must find the difference between the numbers, for example if the numbers were 3, 5, 7, 9, 11 then it would be 2. All you have to do is find out the difference between 2 and the first number, which happens to be 3. So 3-2 equals 1.so the equation would be2n+1you always use n for the nth sequence term
1, 3, 6, 10, 15 ,21 The nth term for the sequence (where you replace n with the term you want to find) is: (n(n+1))/2
what term is formed by multiplying a term in a sequence by a fixed number to find the next term
a + 99d where 'a' is the first term of the sequence and 'd' is the common difference.
The 90th term of the arithmetic sequence is 461
1/6 n(n+1)(n+2)
The sequence is Un = 19 - 3n so the 20th term is 19 - 3*20 = 19 - 60 = -41
If the nth term is 8 -2n then the 1st four terms are 6, 4, 2, 0 and -32 is the 20th term number
you must find the pattern of the sequence in order to find the next 50 terms using that pattern and the first part of the sequence given
If the sequence is non-linear, you need to establish how it is defined.