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(p, q) is point such that p and q are integers, `p ge 50` and the equation `px^(2)+qx+1=0` has real roots. Square of the least distance of the point from the origin is

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To solve the problem, we need to find the square of the least distance of the point (p, q) from the origin, given that p and q are integers, \( p \geq 50 \), and the quadratic equation \( px^2 + qx + 1 = 0 \) has real roots. ### Step-by-step Solution: 1. **Understanding the Distance Formula**: The square of the distance from the origin (0, 0) to the point (p, q) is given by: \[ D^2 = p^2 + q^2 \] We need to minimize \( D^2 \). 2. **Condition for Real Roots**: For the quadratic equation \( px^2 + qx + 1 = 0 \) to have real roots, the discriminant must be non-negative. The discriminant \( \Delta \) is given by: \[ \Delta = q^2 - 4p \cdot 1 = q^2 - 4p \] For real roots, we require: \[ q^2 - 4p \geq 0 \implies q^2 \geq 4p \] 3. **Substituting the Minimum Value of p**: Since \( p \geq 50 \), we will take the minimum value \( p = 50 \): \[ q^2 \geq 4 \cdot 50 = 200 \] 4. **Finding Minimum Integer Value of q**: We need to find the smallest integer \( q \) such that \( q^2 \geq 200 \). The smallest integer \( q \) that satisfies this condition is: \[ q = \lceil \sqrt{200} \rceil = \lceil 14.14 \rceil = 15 \] (since \( 15^2 = 225 \) which is greater than 200). 5. **Calculating the Minimum Value of \( D^2 \)**: Now we can calculate \( D^2 \) using \( p = 50 \) and \( q = 15 \): \[ D^2 = p^2 + q^2 = 50^2 + 15^2 = 2500 + 225 = 2725 \] 6. **Conclusion**: The square of the least distance of the point (p, q) from the origin is: \[ \boxed{2725} \]
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