Use uuu-substitution to solve ∫2x(x2+1)3dx\int 2x(x^2+1)^3 dx∫2x(x2+1)3dx. Let u=x2+1u = x^2+1u=x2+1. What is the resulting integral?
∫u3du\int u^3 du∫u3du
∫u4du\int u^4 du∫u4du
∫2u3du\int 2u^3 du∫2u3du
∫14u3du\int \frac{1}{4} u^3 du∫41u3du