(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This doesn't seem too hard but I can't figure it out. I'm trying to write out a power series expansion for a function, and after a bit of math I've got: [tex]f\left(x\right) = 1 - \frac32 + \frac98 - \frac{27}{48} + \frac{81}{384}... = 1 - \frac{3^1}2 + \frac{3^2}{2*4} - \frac{3^3}{2*4*6} + \frac{3^4}{2*4*6*8}...[/tex]

2. Relevant equations

N/A

3. The attempt at a solution

I just don't know how to express 2*4*6*8...etc. mathematically. Help please?

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# Homework Help: Expressing 2*4*6*8*10*etc. mathematically

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