Ok so i have the next exercise.
I didn't had any problems solving a) and b)
What about c?
Can anyone tell me how to resolve it?
I googled it and found out that's Si(x)(whatever that is) and i don't know about what's that since i'm just last grade of high school.
In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.
You may use taylor expansion about t=0 for c)
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."