Is (2^1/2 + 7^1/3)^1/2 irrational?

  • Thread starter trap101
  • Start date
  • Tags
    Irrational
In summary, an irrational number is a real number that cannot be expressed as a simple fraction or ratio of two integers and has a decimal representation that never ends or repeats in a pattern. You can determine if a number is irrational by trying to express it as a fraction or using the square root test. (2^1/2 + 7^1/3)^1/2 is an irrational number because its components cannot be simplified into a rational number. Knowing if a number is irrational is important in mathematics and science, and the irrationality of (2^1/2 + 7^1/3)^1/2 has practical applications in fields such as engineering, finance, and cryptography.
  • #1
trap101
342
0
Hi,

So I proved that 71/3 is irrational, and I know 21/2 is irrational, but how can I show if (21/2 + 71/3)1/2 is irrational?

Hint of where to start?
 
Physics news on Phys.org
  • #2
Never mind, figured it out.
 
  • #3
trap101 said:
Never mind, figured it out.

Can you give a summary as to how you figured it out?

I was working on it after you posted it.
 

1. What is an irrational number?

An irrational number is a real number that cannot be expressed as a simple fraction or ratio of two integers. It is a decimal that never ends or repeats in a pattern.

2. How do you determine if a number is irrational?

To determine if a number is irrational, you can try to express it as a fraction. If the decimal representation of the number never ends or repeats, then it is irrational. Alternatively, you can use the square root test, which states that if a number is not a perfect square, then its square root is an irrational number.

3. Is (2^1/2 + 7^1/3)^1/2 an irrational number?

Yes, (2^1/2 + 7^1/3)^1/2 is an irrational number because neither 2^1/2 nor 7^1/3 can be expressed as a simple fraction, and their sum cannot be simplified into a rational number.

4. Why is it important to know if a number is irrational?

Knowing if a number is irrational is important in various fields of mathematics and science, particularly in geometry and measurement. It also helps in understanding the concept of infinity and the nature of real numbers.

5. How is the irrationality of (2^1/2 + 7^1/3)^1/2 relevant in real life?

The irrationality of (2^1/2 + 7^1/3)^1/2 is relevant in real life when dealing with measurements and calculations involving square roots. It also has applications in fields such as engineering, finance, and cryptography.

Similar threads

  • Calculus and Beyond Homework Help
Replies
9
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
16
Views
2K
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
3K
  • Precalculus Mathematics Homework Help
Replies
30
Views
2K
  • Calculus and Beyond Homework Help
Replies
15
Views
5K
  • Calculus and Beyond Homework Help
Replies
7
Views
2K
  • Calculus and Beyond Homework Help
Replies
2
Views
2K
Back
Top