Identify Integral: Identify the integral to be solved.We need to evaluate the integral ∫(x2+1)23x3dx.
Use Substitution: Use substitution to simplify the integral.Let u=x2+1. Then du=2xdx, which implies (1/2)du=xdx.
Rewrite in terms of u: Rewrite the integral in terms of u.Substitute x2=u−1 into the integral and use the differential substitution from Step 2:∫(x2+1)23x3dx=∫(x2+1)23x2⋅xdx=∫u23(u−1)⋅21du=21∫u23(u−1)du
Split into simpler integrals: Split the integral into two simpler integrals.(1/2) \int((u - 1) / u^{(3/2)}) du = (1/2) \int(u / u^{(3/2)} - 1 / u^{(3/2)}) du\(\newline= (1/2) \int(u^{-1/2} - u^{-3/2}) du\)
Integrate each term: Integrate each term separately.(1/2)∫(u−1/2−u−3/2)du=(1/2)[∫u−1/2du−∫u−3/2du]=(1/2)[2u1/2−2u−1/2/(−1)]=u1/2+u−1/2
Substitute back in x: Substitute back in terms of x.Since u=x2+1, we have:u(1/2)+u(−1/2)=(x2+1)(1/2)+(x2+1)(1/2)1
Write final answer: Write the final answer.The integral ∫(x2+1)23x3dx is equal to (x2+1)21+(x2+1)211+C, where C is the constant of integration.
More problems from Evaluate definite integrals using the chain rule