Which of the following is an irrational number: −1529

, 0.343434..., 2√3
, or 87.9821?

1 answer

To determine which of the given numbers is irrational, let's analyze each option:

  1. −1529: This is a whole number and is therefore a rational number (it can be expressed as the fraction \(-1529/1\)).

  2. 0.343434...: This is a repeating decimal, which can be expressed as the fraction \(\frac{34}{99}\). Therefore, it is also a rational number.

  3. \(2\sqrt{3}\): The square root of 3 (\(\sqrt{3}\)) is known to be an irrational number. Multiplying an irrational number (\(\sqrt{3}\)) by a rational number (2) results in an irrational number. Thus, \(2\sqrt{3}\) is irrational.

  4. 87.9821: This is a finite decimal and can be expressed as the fraction \(\frac{879821}{10000}\), making it a rational number.

Based on the analysis, the irrational number among the options is:

\(2\sqrt{3}\).