Math Problem Statement

\frac{a}{b} $$$$ +\frac{b}{a} $$$$ $$$$ =1 then $$$$ a^3+b^3=

Solution

We are given the equation:

ab+ba=1\frac{a}{b} + \frac{b}{a} = 1

First, let's simplify the left-hand side:

ab+ba=a2+b2ab\frac{a}{b} + \frac{b}{a} = \frac{a^2 + b^2}{ab}

Thus, we now have the equation:

a2+b2ab=1\frac{a^2 + b^2}{ab} = 1

Multiply both sides of this equation by abab:

a2+b2=aba^2 + b^2 = ab

We are asked to find a3+b3a^3 + b^3. We can use the identity for the sum of cubes:

a3+b3=(a+b)(a2ab+b2)a^3 + b^3 = (a + b)(a^2 - ab + b^2)

Since we already know that a2+b2=aba^2 + b^2 = ab, we can substitute abab for a2+b2a^2 + b^2:

a3+b3=(a+b)(a2ab+b2)=(a+b)(0)=0a^3 + b^3 = (a + b)(a^2 - ab + b^2) = (a + b)(0) = 0

Thus, a3+b3=0a^3 + b^3 = 0.

Would you like further details on any part of this solution?

Here are 5 related questions:

  1. What happens if ab+ba1\frac{a}{b} + \frac{b}{a} \neq 1?
  2. How can we generalize this approach for other values of the sum?
  3. Can we solve for specific values of aa and bb?
  4. What if aa and bb are complex numbers?
  5. What is the geometric interpretation of this result?

Tip: Whenever you see an expression like a3+b3a^3 + b^3, remember the identity a3+b3=(a+b)(a2ab+b2)a^3 + b^3 = (a + b)(a^2 - ab + b^2), which simplifies calculations.

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Math Problem Analysis

Mathematical Concepts

Algebra
Equations
Sum of Cubes

Formulas

Sum of cubes: a^3 + b^3 = (a + b)(a^2 - ab + b^2)
Fraction simplification: \frac{a}{b} + \frac{b}{a} = \frac{a^2 + b^2}{ab}

Theorems

Sum of cubes identity

Suitable Grade Level

Grades 9-12