Solve 1729 as Sum of 2 Cubes: Natural Numbers

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SUMMARY

The number 1729 is the smallest positive integer that can be expressed as the sum of two cubes in two distinct ways using natural numbers. The two representations are 1^3 + 12^3 and 9^3 + 10^3. The discussion highlights the analytical approach to solving the equation x^3 + y^3 = 1729 by factoring it as (x + y)(x^2 - xy + y^2). Additionally, there is a mention of using complex numbers and moduli to explore similar problems.

PREREQUISITES
  • Understanding of cubic equations and their properties
  • Familiarity with factoring techniques in algebra
  • Knowledge of complex numbers and their applications
  • Basic number theory concepts related to sums of cubes
NEXT STEPS
  • Research the factorization of cubic expressions using the identity x^3 + y^3 = (x + y)(x^2 - xy + y^2)
  • Explore the historical context and significance of the number 1729 in mathematics
  • Learn about methods for expressing numbers as sums of cubes
  • Investigate the use of complex numbers in solving polynomial equations
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Mathematics students, educators, and enthusiasts interested in number theory, particularly those exploring the properties of cubic equations and their historical significance.

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Homework Statement


1729 is the smallest positive integer that can be represented in two different ways as the sum of two cubes , what are the two ways.
They have to be natural numbers.

The Attempt at a Solution



x^3+Y^3=1729 i could just find the answer by guess and check , but I am not sure how to do it analytically.
 
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You can simplify a little by using x^3+ y^3= (x+ y)(x^2- xy+ y^2).

Now, factor 1729 to find two factors that would fit that.
 
sweet thanks for the help
 
I remember my teacher showing us a method with complex numbers and moduli to find the sum of two squares to equal some number we have. If only I remember the method... Maybe this can be extended to the sum of two cubes?
 
You can't not know the oft-told tale about this question and this number?
 
There is a very oft-told tale about this question with this number many people here will know.
 
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