Evaluating Integral with a natural log

[XedLos]

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Homework Statement

$$\int9s9^s ds$$

Homework Equations

∫udv=uv-∫9^sds-∫vdu

The Attempt at a Solution

u=9s
du=9ds

dv=9^s ds
v=∫9^sds
=∫3^(2s) ds
=3^(2s)/[2ln(3)]
this is as far as i have gotten. Am i correct so far?

 

[HallsofIvy]

Yes, that is correct. You didn't really need to reduce to 3, that is exactly the same as
$$\int 9^s ds= 9^s/ln(9)$$