1. Recall the ring of function $R = F(\mathbb{R}, \mathbb{R})$. Prove that the subset
$I = \{f : \mathbb{R} \to \mathbb{R}|f(0) = 0\}$
is an ideal of R. Consider the quotient ring R/I. For the following functions f and g, determine
(with proof) whether $[f] = [g]$ in the quotient ring R/I.
(a) $f = e^x$ and $g = \sin(x)$
(b) $f = x^2 + 1233442x - 23234$ and $g = 33x^5 - 42x^4 + 47x^2 + 3345$
(c) $f = \frac{1}{x^2+1}$ and $g = \cos(x)$