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1. Why would rational coefficients of a quadratic equation never get repeated irrational roots?
2. For a repeated root, the discriminant is equal to 0, and the repeated root is simply -b/2a, where ax^2 + bx + c = 0. Hence if a, b, c are rational, then -b/2a (the repeated root) must also be rational.
3. (Original post by Simba)
For a repeated root, the discriminant is equal to 0, and the repeated root is simply -b/2a, where ax^2 + bx + c = 0. Hence if a, b, c are rational, then -b/2a (the repeated root) must also be rational.
Thanks

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