Identify Integral: Identify the integral to be solved.We need to evaluate the integral of the function (2x+1)x2+2x+21 with respect to x.
Simplify Expression: Simplify the expression under the square root.Notice that x2+2x+1 can be written as (x+1)2+1, which is a sum of squares.
Use Substitution: Use substitution to simplify the integral.Let u=x+1, which implies du=dx. Then the integral becomes:∫(2(u−1)+1)u2+11du
Simplify Integral: Simplify the expression in the integral.The integral now is:∫(2u−1)u2+11du
Use Another Substitution: Use another substitution to transform the integral into a standard form.Let u2+1=v2, which implies 2udu=2vdv. Then the integral becomes:∫(2v2−2)v21⋅(vdv)
Simplify Expression: Simplify the expression in the integral.The integral now is:∫2v2−21dv
Factor Out Constant: Factor out the constant from the denominator.The integral now is:(\frac{\(1\)}{\(2\)})\int \frac{\(1\)}{v^\(2\)\(-1\)} \, dv
Decompose Integrands: Decompose the integrand into partial fractions. The integral now is: \((\frac{1}{2})\int \frac{1}{(v-1)(v+1)} dv This can be decomposed into v−1A+v+1B.
Find Constants: Find the constants A and B. By setting up the equation: 1=A(v+1)+B(v−1) and solving for A and B when v=1 and v=−1, we get A=21 and B=−21.
Write with Partial Fractions: Write the integral with the partial fractions.The integral now is:(\frac{\(1\)}{\(2\)})\int(\frac{\(1\)}{\(2\)})/(v\(-1) - (\frac{1}{2})/(v+1)) \, dv
Integrate Term by Term: Integrate term by term.The integral now is:(41)ln∣v−1∣−(41)ln∣v+1∣+C
Substitute Back for v: Substitute back for v and then for u.Substituting back for v, we get:(41)ln∣u2−1∣−(41)ln∣u2+1∣+CAnd then substituting back for u, we get:(41)ln∣(x+1)2−1∣−(41)ln∣(x+1)2+1∣+C
Substitute Back for u: Simplify the final expression.The final answer is:(\frac{\(1\)}{\(4\)})\ln|x^\(2+2x| - (\frac{1}{4})\ln|x^2+2x+2| + C
More problems from Evaluate definite integrals using the chain rule