Identify Integral: Identify the integral to be solved.We need to evaluate the integral of the function x3+3x+20x2+1 with respect to x.
Find Substitution: Look for a substitution that simplifies the integral.Let u=x3+3x+20, then dxdu=3x2+3. Notice that x2 is part of the derivative of u, which suggests that this substitution might be useful.
Express x2: Express x2 in terms of u and du.Since dxdu=3x2+3, we can solve for x2: x2=3du/dx−3. We will use this expression to replace x2 in the integral.
Perform Substitution: Perform the substitution in the integral.Substitute u for x3+3x+20 and (dxdu−3)/3 for x2 in the integral. The integral becomes:∫(3dxdu−3+1)/udx
Simplify Integral: Simplify the integral.The integral simplifies to:∫(31dxdu−1+1)/udx= ∫(31dxdu)/udx= 31∫udu
Integrate with u: Integrate with respect to u. The integral of u1 with respect to u is 2u, so we have: 31×2×u+C=(32)×u+C
Substitute back: Substitute back for u. Replace u with x3+3x+20 to get the final answer: 32⋅x3+3x+20+C
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