Identify type of integral: Identify the type of integral.We are asked to integrate a product of a polynomial function, x2, and an exponential function, e2x. This suggests that we should use integration by parts.
Apply integration by parts: Apply the integration by parts formula.The integration by parts formula is ∫udv=uv−∫vdu, where u and dv are parts of the integrand that we choose. We need to choose u and dv such that du and v are easy to work with.
Choose u and dv: Choose u and dv. Let's choose u=x2 (which means du=2xdx after differentiation) and dv=e2xdx (which means v=(1/2)e2x after integration).
Differentiate and integrate: Differentiate u and integrate dv.Differentiate u to get du=2xdx.Integrate dv to get $v = \left(\frac{\(1\)}{\(2\)}\right)e^{\(2\)x}.
Substitute into formula: Substitute \(u\), \(du\), \(v\), and \(dv\) into the integration by parts formula.\(\newline\)Substitute the values into the formula to get:\(\newline\)\(\int x^2 e^{2x} dx = x^2 \cdot (\frac{1}{2})e^{2x} - \int(\frac{1}{2})e^{2x} \cdot 2x dx\)
Simplify expression: Simplify the expression.\(\newline\)Simplify the integral to get:\(\newline\)\(\int x^2 e^{2x} \, dx = \frac{1}{2}x^2 e^{2x} - \int x e^{2x} \, dx\)
Apply integration by parts again: Apply integration by parts again to the remaining integral.\(\newline\)We need to apply integration by parts to \(\int x e^{2x} \, dx\). Let's choose \(u = x\) (\(du = dx\)) and \(dv = e^{2x} dx\) (\(v = (1/2)e^{2x}\)).
Differentiate and integrate: Differentiate \(u\) and integrate \(dv\) for the second application of integration by parts.\(\newline\)Differentiate \(u\) to get \(du = dx\).\(\newline\)Integrate \(dv\) to get \(v = \frac{1}{2}e^{2x}\).
Substitute into formula again: Substitute \(u\), \(du\), \(v\), and \(dv\) into the integration by parts formula for the second time.\(\newline\)Substitute the values into the formula to get:\(\newline\)\(\int x e^{2x} dx = x \cdot (\frac{1}{2})e^{2x} - \int(\frac{1}{2})e^{2x} dx\)
Simplify and integrate: Simplify the expression and integrate the remaining term.\(\newline\)Simplify the integral to get:\(\newline\)\(\int x e^{2x} dx = \frac{1}{2}x e^{2x} - \frac{1}{4}e^{2x}\)
Substitute result back: Substitute the result from Step \(10\) back into the expression from Step \(6\).\(\newline\)Substitute the result to get:\(\newline\)\(\int x^2 e^{2x} dx = \frac{1}{2}x^2 e^{2x} - \left[\frac{1}{2}x e^{2x} - \frac{1}{4}e^{2x}\right]\)
Simplify final expression: Simplify the final expression.\(\newline\)Simplify the expression to get:\(\newline\)\(\int x^2 e^{2x} dx = \frac{1}{2}x^2 e^{2x} - \frac{1}{2}x e^{2x} + \frac{1}{4}e^{2x} + C\), where \(C\) is the constant of integration.
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