# Math Help - Prove something is an ideal

1. ## Prove something is an ideal

If I is an ideal in R, is I[x] (polynomials with coefficients in I) an ideal in the polynomial ring R[x]?

2. Originally Posted by iwonde
If I is an ideal in R, is I[x] (polynomials with coefficients in I) an ideal in the polynomial ring R[x]?

Yes, and the proof is trivial. Try it.

Tonio

3. Originally Posted by tonio
Yes, and the proof is trivial. Try it.

Tonio
I'm sorry to mention this but I don't see how this is shown. Can anyone prove this?