Derive the nth term of a sequence

AI Thread Summary
To derive the nth term of a sequence from the sum to the nth term, one can use the relationship between consecutive sums. For example, if Sum4 equals a1 + a2 + a3 + a4 and Sum3 equals a1 + a2 + a3, then a4 can be expressed as a4 = Sum4 - Sum3. This method allows for the calculation of any term in the sequence by subtracting the sum of the previous terms from the current sum. The discussion emphasizes using specific examples to clarify the process. Understanding this relationship is crucial for deriving general equations for sequences.
Aceix
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How do i go about deriving a general eqn for the nth term of a sequence provided an eqn of the sum to the nth term is given in terms of n?
 
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Rather than give you the answer, try a discrete example. Think of it this way. I know:
Sum4 = a1+a2+a3+a4
and I know
Sum3 = a1+a2+a3 .

How would I find a4 in terms of Sum4 and Sum3?
 
phyzguy said:
Rather than give you the answer, try a discrete example. Think of it this way. I know:
Sum4 = a1+a2+a3+a4
and I know
Sum3 = a1+a2+a3 .

How would I find a4 in terms of Sum4 and Sum3?
 
Does your blank reply mean you don't know?
 
phyzguy said:
Does your blank reply mean you don't know?

i meant thanks.

Aceix.
 
OK. You're welcome.
 
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