Prove that the product of three pie and 2/5 is an irrational number find the product and explain why the value is irrational

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 months ago

To prove that the product of \(3\pi\) and \(\frac{2}{5}\) is an irrational number, we start by calculating the product:

\[
3\pi \times \frac{2}{5} = \frac{6\pi}{5}
\]

Next, we need to establish why \(\frac{6\pi}{5}\) is irrational.

1. **Understanding the components**:
- \(\pi\) (pi) is known to be an irrational number. By definition, an irrational number cannot be expressed as a fraction of two integers, meaning it cannot be represented in the form \(\frac{a}{b}\), where \(a\) and \(b\) are integers and \(b \neq 0\).

2. **Properties of irrational numbers**:
- The product of a non-zero rational number and an irrational number is always irrational. Since \(\frac{6}{5}\) is a rational number (where \(6\) and \(5\) are integers, and \(5 \neq 0\)), we can use this property.

3. **Applying the property**:
- We know that \( \pi \) is irrational and \( \frac{6}{5} \) is rational. Thus, we compute the product:
\[
\frac{6\pi}{5} = \frac{6}{5} \cdot \pi
\]
- Since \(\frac{6}{5}\) is rational and \(\pi\) is irrational, \(\frac{6\pi}{5}\) must also be irrational.

Therefore, \(\frac{6\pi}{5}\) is an irrational number because it is the product of a rational number \( \frac{6}{5} \) and an irrational number \( \pi \).

### Conclusion
The product \(3\pi \times \frac{2}{5} = \frac{6\pi}{5}\) is irrational because it results from multiplying a rational number by an irrational number.