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UKMT Senior Kangaroo, 2024

Algebra Difficulty 1.0 Junior Prove it United Kingdom

What is the value of $|\sqrt{123} - 456| + |\sqrt{123} + 456|$ ? The modulus function, $|x|$ is given by $|x| = x$ for $x \geq 0$ , and $|x| = -x$ for $x < 0$ .

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