Identify Integral: Let's start by identifying the integral we need to evaluate:I=∫−2xe(3x+2)dxWe can use integration by parts, which states that ∫udv=uv−∫vdu, where u and dv are parts of the integrand we choose to differentiate and integrate, respectively.Let's choose u=−2x (which will be differentiated) and dv=e(3x+2)dx (which will be integrated).
Choose u and dv: Differentiate u with respect to x to find du: u=−2x dxdu=−2 du=−2dx
Differentiate u: Integrate dv with respect to x to find v: dv=e(3x+2)dx To integrate e(3x+2), we need to use the substitution method. Let w=3x+2, then dxdw=3, dx=3dw. v=∫e(3x+2)dx=∫ew⋅(3dw)=(31)ew+C Substitute back w=3x+2: dv1
Integrate dv: Now apply the integration by parts formula:I=uv−∫vduI=(−2x)(31)e(3x+2)−∫(31)e(3x+2)(−2dx)I=(−32)xe(3x+2)+(32)∫e(3x+2)dx
Apply Integration by Parts: We have already found the integral of e3x+2dx when we calculated v, so we can use that result:I=(−32)xe3x+2+(32)(31e3x+2)+CI=(−32)xe3x+2+(92)e3x+2+C
Use Result for Integral: Combine the terms with the common factor e3x+2:I=e3x+2(3−2x+92)+C
Combine Terms: Simplify the expression inside the parentheses:I=e(3x+2)(9−6x+92)+CI=e(3x+2)(9−6x+2)+C
Simplify Expression: Factor out the common factor of 91:I=(91)e(3x+2)(−6x+2)+C
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