Identify Substitution: Let's start by identifying a substitution that will simplify the integral. We can let u=1+ln(x), which implies that du=(x1)dx. This substitution will simplify the integral significantly.
Find Limits for u: Now, we need to find the corresponding limits of integration for u. When x=1, u=1+ln(1)=1. When x=2, u=1+ln(2). So, the new limits of integration are from u=1 to u=1+ln(2).
Substitute u into Integral: Substitute u=1+ln(x) and du=(x1)dx into the integral. The integral becomes:∫(1+ln(x))2⋅x1+2ln(x)dx=∫u21+2(u−1)du
Simplify Integral: Simplify the integral: \int\left(\frac{1+2(u−1)}{u^2}\right) du = \int\left(\frac{1+2u−2}{u^2}\right) du = \int\left(\frac{1}{u^2} + \frac{2u}{u^2} - \frac{2}{u^2}\right) du = \int\left(\frac{1}{u^2} + \frac{2}{u} - \frac{2}{u^2}\right) du = \int\left(\frac{2}{u} - \frac{1}{u^2}\right) du
Integrate Term by Term: Now, integrate term by term: ∫(u2−u21)du=2∫(u1)du−∫(u21)du=2ln∣u∣−(u1)+C
Substitute back to x: Substitute back u=1+ln(x) to get the antiderivative in terms of x:2ln∣u∣−(1/u)+C=2ln∣1+ln(x)∣−1/(1+ln(x))+C
Evaluate Definite Integral: Evaluate the definite integral from u=1 to u=1+ln(2):[2ln∣1+ln(x)∣−1+ln(x)1]x=1x=2=(2ln(1+ln(2))−1+ln(2)1)−(2ln(1)−11)=(2ln(1+ln(2))−1+ln(2)1)−(0−1)=2ln(1+ln(2))−1+ln(2))1+1
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