Recognize problem type: Recognize the integral as an integration by parts problem. Integration by parts formula is ∫udv=uv−∫vdu. Let u=−x and dv=e(−x+4)dx.
Define u and dv: Differentiate u and integrate dv. du=−dx and v=∫e(−x+4)dx. To integrate dv, we need to find the antiderivative of e(−x+4).
Differentiate and integrate: Calculate the antiderivative of e(−x+4).v=∫e(−x+4)dx=e(−x+4)⋅(−1)=−e(−x+4).
Calculate antiderivative: Apply the integration by parts formula.∫udv=uv−∫vdu.Substitute u, du, and v into the formula.
Apply integration by parts: Perform the substitution and simplify. ∫−xe(−x+4)dx=−x(−e(−x+4))−∫(−e(−x+4))(−dx). Simplify the expression.
Perform substitution: Simplify the expression further.∫−xe(−x+4)dx=xe(−x+4)−∫e(−x+4)dx.Now we need to integrate e(−x+4) with respect to x.
Simplify expression: Integrate e(−x+4) with respect to x.∫e(−x+4)dx=e(−x+4)×(−1)=−e(−x+4).
Integrate e(−x+4): Substitute the integral back into the expression.xe(−x+4)−∫e(−x+4)dx=xe(−x+4)−(−e(−x+4)).
Substitute integral back: Simplify the final expression and add the constant of integration. xe(−x+4)+e(−x+4)+C.
Simplify final expression: Write the final answer.The integral of −xe(−x+4) with respect to x is xe(−x+4)+e(−x+4)+C.
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