I'd just like some verification that I did this right. The answer I got is a bit bizarre, but I'm not seeing any issues in my math.

the equation is

the composite I'm supposed to solve is

so I plug 3 into the function and get

then plug that back in and get

I think I'm doing the math right, but that's not typically the kind of answer you'll find when solving problem for class, so I just wanted some verification I hadn't gone off kilter somewhere.

*edited* made a mistake, recalculated, adjusted the above to reflect what I think is correct math