I found this problem and I don't understand the solution. I will appreciate your help. Let $A = \mathbb{Q}[X_1,...,X_n,...], a = (X_1^2,...,X_n^2,...)$ and $ M = A/a$. Show that $Ass_A (M) = \emptyset $. Why isn't $Ass_A(M) = (X_1,...,X_n,...)$ ?
I'm writing this because the site is giving me this error : "Oops! Your question couldn't be submitted because:
* It does not meet our quality standards.". This feels verry strange!!!