determine if expression is polynomial P(x,y/Q(x,y)



On 2/25/2012 9:34 AM, Stavros Macrakis wrote:
>   But beware of things like trigonometric identities (as RJF says), 
> radicals, etc.
>
>               -s
>
One of my favorite polynomial-producing expressions is along the lines 
of cos(p*acos(x)).

For example,  trigexpand(cos(5*acos(x))  is 
5*x*(1-x^2)^2+x^5-10*x^3*(1-x^2) = 16*x^5-20*x^3+5*x