Set up integration by parts: Let's use integration by parts to evaluate the integral of −6xe−x with respect to x. Integration by parts is given by the formula ∫udv=uv−∫vdu, where u and dv are parts of the integrand that we choose. We will let u=−6x and dv=e−xdx. Then we need to find du and v.Calculating du and v:x1 (derivative of x2 with respect to x)x4 (antiderivative of x5 with respect to x)
Calculate du and v: Now we apply the integration by parts formula:∫−6xe−xdx=uv−∫vduSubstituting the values of u, v, du, and dv we found:∫−6xe−xdx=(−6x)(−e−x)−∫(−e−x)(−6)dxSimplifying the expression:∫−6xe−xdx=6xe−x−∫6e−xdx
Apply integration by parts: Next, we integrate the remaining integral ∫6e−xdx. The antiderivative of 6e−x with respect to x is −6e−x, since the derivative of −6e−x is 6e−x.So, ∫6e−xdx=−6e−x+C, where C is the constant of integration.
Integrate remaining integral: Now we combine the results from the previous steps:∫−6xe−xdx=6xe−x−(−6e−x+C)Simplifying the expression:∫−6xe−xdx=6xe−x+6e−x+C
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