Express the limit as a definite integral on the given interval.

nx_{i}ln(1 +x_{i}^{2}) Δx, [0, 4]http://www.webassign.net/wastatic/wa...ex/img/sum.gif i= 1

My work: I figured out that f(x) = xln(1+x^2)

therefore we need to find the integral from 0 to 4 of xln(1+x^2)dx

I'm a little confused. Do I start by making a graph? I haven't memorized the log graphs so sorry for my naivety. I appreciate any help.