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If omega is the imaginary cube roots o...

If `omega ` is the imaginary cube roots of unity, then the number of pair of integers (a,b) such that `|aomega + b| = 1` is ______.

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To solve the problem, we need to find the number of ordered pairs of integers \((a, b)\) such that \(|a\omega + b| = 1\), where \(\omega\) is a non-real cube root of unity. ### Step-by-Step Solution: 1. **Understanding the Cube Roots of Unity**: The cube roots of unity are the solutions to the equation \(x^3 = 1\). They are given by: \[ 1, \quad \omega = e^{2\pi i / 3} = -\frac{1}{2} + i\frac{\sqrt{3}}{2}, \quad \omega^2 = e^{-2\pi i / 3} = -\frac{1}{2} - i\frac{\sqrt{3}}{2} \] Here, \(\omega^3 = 1\) and \(1 + \omega + \omega^2 = 0\). 2. **Setting Up the Equation**: We start with the equation: \[ |a\omega + b| = 1 \] Squaring both sides gives: \[ |a\omega + b|^2 = 1^2 \] This implies: \[ (a\omega + b)(a\overline{\omega} + b) = 1 \] Since \(\overline{\omega} = \omega^2\), we rewrite this as: \[ (a\omega + b)(a\omega^2 + b) = 1 \] 3. **Expanding the Left Side**: Expanding the left-hand side: \[ a^2(\omega \cdot \omega^2) + ab(\omega + \omega^2) + b^2 = 1 \] Since \(\omega \cdot \omega^2 = 1\) and \(\omega + \omega^2 = -1\), we have: \[ a^2 + ab(-1) + b^2 = 1 \] Simplifying gives: \[ a^2 - ab + b^2 = 1 \] 4. **Rearranging the Equation**: We can rearrange this equation as: \[ a^2 - ab + b^2 - 1 = 0 \] 5. **Finding Integer Solutions**: We can treat this as a quadratic in \(a\): \[ a^2 - ab + (b^2 - 1) = 0 \] The discriminant of this quadratic must be a perfect square for \(a\) to be an integer: \[ D = b^2 - 4(b^2 - 1) = -3b^2 + 4 \] Setting \(D = k^2\) for some integer \(k\): \[ 4 - 3b^2 = k^2 \implies 3b^2 + k^2 = 4 \] 6. **Finding Integer Pairs**: We need to find integer pairs \((b, k)\) such that \(3b^2 + k^2 = 4\): - If \(b = 0\), then \(k^2 = 4 \Rightarrow k = \pm 2\). - If \(b = 1\), then \(3 + k^2 = 4 \Rightarrow k^2 = 1 \Rightarrow k = \pm 1\). - If \(b = -1\), it gives the same results as \(b = 1\). - If \(b = 2\) or \(|b| > 2\), then \(3b^2 > 4\), which is not possible. The valid pairs are: - For \(b = 0\): \(k = 2\) or \(-2\) gives \(a^2 = 1\) leading to \((1, 0)\) and \((-1, 0)\). - For \(b = 1\): \(k = 1\) or \(-1\) gives \(a^2 = 1\) leading to \((1, 1)\) and \((-1, 1)\). - For \(b = -1\): similar to \(b = 1\) gives \((1, -1)\) and \((-1, -1)\). 7. **Counting Ordered Pairs**: The pairs we found are: - \((1, 0)\), \((-1, 0)\) - \((1, 1)\), \((-1, 1)\) - \((1, -1)\), \((-1, -1)\) - \((0, 1)\), \((0, -1)\) - \((1, 0)\), \((0, 1)\) Thus, the total number of ordered pairs \((a, b)\) is \(6\). ### Final Answer: The number of pairs of integers \((a, b)\) such that \(|a\omega + b| = 1\) is **6**.

To solve the problem, we need to find the number of ordered pairs of integers \((a, b)\) such that \(|a\omega + b| = 1\), where \(\omega\) is a non-real cube root of unity. ### Step-by-Step Solution: 1. **Understanding the Cube Roots of Unity**: The cube roots of unity are the solutions to the equation \(x^3 = 1\). They are given by: \[ 1, \quad \omega = e^{2\pi i / 3} = -\frac{1}{2} + i\frac{\sqrt{3}}{2}, \quad \omega^2 = e^{-2\pi i / 3} = -\frac{1}{2} - i\frac{\sqrt{3}}{2} ...
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