Question: how to find the formula for the nth term of a quadratic sequence?
Answer: So, the nth term formula will take the form a n 2 + b n + c an^2+bn+c an2+bn+c, where a , b , a, b, a,b, and c are numbers for us determine. ... 
We now know the nth term formula is u n = n 2 + b n + c u_n=n^2+bn+c un=n2+bn+c, so we still need to find b and c.