Calculus
posted by Jacob .
Find a number X such that the error is less than X (The error is 14593/2340 for the sequence, 7n/(n^3+1).
How would you start to solve this problem?

The error in what? Where did you get the number 14593/2340? I don't understand the question. Please make sure you stated it correctly.
Are you trying to approximate the sum of an infinite series? 
Our teacher told us that the fourth partial sum approximates the sum of the sequence 7n/(n^3+1). The fourth partial sum is also the error of the sequence and our teacher asks us to find a number X such that the error is less than X.