Classify the following numbers as rational or irrational:(i) `2-sqrt(5)` (ii) `(3+sqrt(23))-sqrt(23)` (iii) `(2sqrt(7))/(7sqrt(7))` (iv) `1/(sqrt(2))` (v) `2pi`

Explanation

To classify the given numbers as rational or irrational, we will analyze each part step by step.

### Step-by-Step Solution:

**(i) \(2 - \sqrt{5}\)**
1. Identify \(\sqrt{5}\): It is known that \(\sqrt{5}\) is an irrational number.
2. Since 2 is a rational number, and the subtraction of a rational number (2) and an irrational number (\(\sqrt{5}\)) results in an irrational number, we conclude that \(2 - \sqrt{5}\) is irrational.

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