If f(x) were reducible, then we would have f(x)= g(x)h(x) for some g and h in F(x). But then f(cx)= g(cx)h(cx).
Hello there!!
Can you prove this problem?,
Let the set F be a field and let c be a nonzero element of the set F. If f(cx) is irreducible over the set F, prove that f(x) is irreducible of over the set F.