Concept:
To solve this integral, we simplify the expression inside the square root and use appropriate algebraic manipulations or substitutions to transform it into a standard integral form.
Step 1: Simplify the expression inside the square root.
Factor out \(x^2\) from the square root:
\[
\sqrt{x^4 + 2x^3 + 2x^2} = \sqrt{x^2(x^2 + 2x + 2)} = x\sqrt{x^2 + 2x + 2}
\]
So the integral becomes:
\[
I = \int \frac{1}{x\sqrt{x^2 + 2x + 2}} \, dx
\]
Step 2: Apply substitution to simplify the integrand.
Let \(x = \frac{1}{t}\), then \(dx = -\frac{1}{t^2} dt\). Substituting these into the integral:
\[
I = \int \frac{1}{(1/t)\sqrt{(1/t)^2 + 2(1/t) + 2}} \left(-\frac{1}{t^2}\right) \, dt
\]
\[
I = -\int \frac{1}{t\sqrt{\frac{1 + 2t + 2t^2}{t^2}}} \, dt = -\int \frac{1}{\sqrt{2t^2 + 2t + 1}} \, dt
\]
Step 3: Complete the square and integrate.
Factor out \(\sqrt{2}\) from the square root:
\[
I = -\frac{1}{\sqrt{2}} \int \frac{1}{\sqrt{t^2 + t + 1/2}} \, dt
\]
Completing the square for \(t^2 + t + 1/2 = (t + 1/2)^2 + 1/4\):
\[
I = -\frac{1}{\sqrt{2}} \int \frac{1}{\sqrt{(t + 1/2)^2 + (1/2)^2}} \, dt
\]
Using the standard integral \(\int \frac{1}{\sqrt{u^2 + a^2}} du = \sinh^{-1}(u/a)\):
\[
I = -\frac{1}{\sqrt{2}} \sinh^{-1}\left(\frac{t + 1/2}{1/2}\right) + c = -\frac{1}{\sqrt{2}} \sinh^{-1}(2t + 1) + c
\]
Since \(t = 1/x\):
\[
I = -\frac{1}{\sqrt{2}} \sinh^{-1}\left(\frac{2}{x} + 1\right) + c = -\frac{1}{\sqrt{2}} \sinh^{-1}\left(\frac{x + 2}{x}\right) + c
\]
Conclusion:
The value of the integral is \( -\frac{1}{\sqrt{2}} \sinh^{-1}\left(\frac{x+2}{x}\right) + c \).
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Final Answer: (A) -12 ^-1(x+2x) + c
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