b) \( [2+3 \) marks \( ] \) Let \( f: \mathbb{R} \backslash\{0\} \rightarrow \mathbb{R} \backslash\{1\} \) be a function defined by \( f(x)=\frac{x+2}{x} \). i. Show that \( f \) is onto. ii. Show tha