The value of ∫−11(1+∣x∣−x)ex+(∣x∣−x)e−xex+e−x\int_{-1}^{1} \frac{(1 + \sqrt{|x|} - x)e^x + (\sqrt{|x|} - x)e^{-x}}{e^x + e^{-x}} \, dx is equal to:

Answer: 73\frac{7}{3}

Step-by-step solution

Step 1: Split the integrand

First, we can split the given integral into two parts. The first part contains the exe^x term from the numerator, and the second part contains the remaining terms. This separation helps simplify the expression.

Step 2: Simplify the second integral

In the second integral, we can factor out (∣x∣−x)(\sqrt{|x|} - x) from the numerator, which simplifies the expression to (∣x∣−x)ex+e−xex+e−x=(∣x∣−x)(\sqrt{|x|} - x) \frac{e^x + e^{-x}}{e^x + e^{-x}} = (\sqrt{|x|} - x).

Step 3: Split the second integral further

We can further split the second integral into two separate integrals: one for ∣x∣\sqrt{|x|} and one for xx. This allows us to evaluate each part individually.

Step 4: Evaluate integrals of odd and even functions

For an integral from −a-a to aa: if f(x)f(x) is an odd function (f(−x)=−f(x)f(-x) = -f(x)), then ∫−aaf(x) dx=0\int_{-a}^{a} f(x) \, dx = 0. Since xx is an odd function, ∫−11x dx=0\int_{-1}^{1} x \, dx = 0. If f(x)f(x) is an even function (f(−x)=f(x)f(-x) = f(x)), then ∫−aaf(x) dx=2∫0af(x) dx\int_{-a}^{a} f(x) \, dx = 2 \int_{0}^{a} f(x) \, dx. Since ∣x∣\sqrt{|x|} is an even function, ∫−11∣x∣ dx=2∫01x dx\int_{-1}^{1} \sqrt{|x|} \, dx = 2 \int_{0}^{1} \sqrt{x} \, dx.

Step 5: Evaluate the remaining integrals

For the first integral, multiply the numerator and denominator by exe^x. Let u=e2x+1u = e^{2x} + 1, then du=2e2x dxdu = 2e^{2x} \, dx. The integral becomes 12∫1u du=12ln⁡∣u∣\frac{1}{2} \int \frac{1}{u} \, du = \frac{1}{2} \ln|u|. Evaluating from −1-1 to 11 gives 12[ln⁡(e2x+1)]−11=12(ln⁡(e2+1)−ln⁡(e−2+1))\frac{1}{2} [\ln(e^{2x} + 1)]_{-1}^{1} = \frac{1}{2} (\ln(e^2+1) - \ln(e^{-2}+1)). For the second integral, we evaluate ∫x1/2 dx=x3/23/2=23x3/2\int x^{1/2} \, dx = \frac{x^{3/2}}{3/2} = \frac{2}{3} x^{3/2} from 00 to 11.

Step 6: Combine the results

Substitute the evaluated values back into the expression for II. The logarithmic terms simplify to 11. The term 2×232 \times \frac{2}{3} becomes 43\frac{4}{3}.

Step 7: Final Calculation

Add the simplified terms to get the final value of the integral.

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