Identify integral: Identify the integral that needs to be evaluated.The integral to be evaluated is ∫−2xe4xdx.
Recognize form: Recognize that the integral is in the form suitable for integration by parts. Integration by parts is given by the formula ∫udv=uv−∫vdu, where u and dv are parts of the integrand.
Choose u and dv: Choose u and dv.Let u=−2x, which implies du=−2dx.Let dv=e4xdx, which implies v=41e4x after integrating dv.
Apply integration by parts: Apply the integration by parts formula.Using the integration by parts formula, we get:∫−2xe4xdx=uv−∫vdu=(−2x)(41)e4x−∫(41)e4x(−2dx)=(−21)xe4x+(21)∫e4xdx
Integrate remaining integral: Integrate the remaining integral.The remaining integral is ∫e4xdx, which is 41e4x after integration.
Substitute result: Substitute the result of the integration back into the equation.Substituting the result from Step 5 into the equation from Step 4, we get:∫−2xe4xdx=(−21)xe4x+(21)(41)e4x+C=(−21)xe4x+81e4x+C
Combine final answer: Combine like terms and write the final answer.The final answer is:\int \(-2xe^{4x}\,dx = \left(-\frac{1}{2}\right)xe^{4x} + \left(\frac{1}{8}\right)e^{4x} + C
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