Question 1118910
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That is the product of two binomial conjugates, hence the difference of two squares.  n.b. *[tex \Large (a\ +\ b)(a\ -\ b)\ =\ a^2\ -\ b^2]
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
{{n}\choose{r}}
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