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Prove root 5 is irrational number?
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Prove root 5 is irrational number?
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Prove root 5 is irrational number?
Proving Root 5 is Irrational Number



  • Definition of Irrational Number

  • An irrational number is a number that cannot be expressed as a ratio of two integers.


  • Assume root 5 is rational

  • Let's assume that root 5 is a rational number, which means it can be expressed in the form of p/q, where p and q are integers with no common factors and q is not equal to zero.


  • Squaring both sides

  • Squaring both sides of the equation root 5 = p/q, we get:

    5 = p^2/q^2


  • Deriving a contradiction

  • If 5 = p^2/q^2, then p^2 = 5q^2. This means that p^2 is divisible by 5. Therefore, p must be divisible by 5 as well.

    Let p = 5k (where k is an integer)

    Substituting p = 5k in the equation p^2 = 5q^2, we get:

    25k^2 = 5q^2

    5k^2 = q^2

    This means that q^2 is divisible by 5. Therefore, q must also be divisible by 5.

    However, this contradicts our earlier assumption that p and q have no common factors. Therefore, our assumption that root 5 is a rational number is false.


  • Conclusion

  • Therefore, we can conclude that root 5 is an irrational number.


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Prove root 5 is irrational number?
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