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Evaluate the integral using integration by parts with the indicated choices of u and dv. (Use c for the constant of integration.)

1) x²e⁹x + ce⁹x
2) xe⁹x - 9e⁹x + c
3) xe⁹x + 9e⁹x + c
4) x²e⁹x - 9e⁹x + c

User Cmp
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1 Answer

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Final answer:

To evaluate the integral using integration by parts, choose
u = x^2 and
dv = e^9x dx. Apply the integration by parts formula to find the integral step-by-step.

Step-by-step explanation:

To evaluate the given integral using integration by parts, we need to choose u and dv.

Let
u = x^2 and
dv = e^9x dx.

Then, du = 2x dx and
v = (1/9)e^9x.

Using the integration by parts formula:


\int {u} \, dv = uv -\int {v} \, du


\int\ {x^2e^9x} \, dx = (x^2)(1/9)e^9x - \int\ {(1/9)e^9x(2x)} \, dx

=
(1/9)x^2e^9x - (2/9)\int\ {x^2e^9x} \, dx

Now we have a similar integral as the one we started with. We can repeat the process of integration by parts to evaluate the remaining integral.

So, the correct choice is option 4)
x^2e^9x - 9e^9x + c

User Sjoerd
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