lny = x²ln(1+x)
y'/y = 2xln(1+x) +x²/(1+x)
y' = [2xln(1+x) +x²/(1+x)]y = [2xln(1+x) +x²/(1+x)](1+x)^x²
= 2x(1+x)^x^2*ln(1+x) + x²(1+x)^(x²-1)