I need some help(adsbygoogle = window.adsbygoogle || []).push({});

I got an expression involving series...

x - (2/6)x^3 - (20/120)x^5 - (1080/5040)x^7 - (140400/362880)x^9 - ...

I remove x from my summation expression.. but

Right now, I can express as a summation from n = 1 to infinity of

(??) x^(2n + 1) / (2n + 1)!

That is.. what is my pattern in this: 2, 20, 1080, 140400,... ?

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# Homework Help: Simplify as one expression

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