Hi Marek,

this is not a help or Q&A site, sorry! Perhaps you were looking for math.stackexchange? If you ask there, please look around first and see if your question is already answered, or, if not, see what is considered a good way to ask your question.

]]>We consider subset I_a of R consisting of polynomials vanishing at a point a∉{0,1} how I can prove that is it a prime ideal?

and the set of polynomials vanishing at 0 and 1 why is also a prime ideal? How I can prove it? ]]>