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    Quadratic Equation Solver

    Find the roots of any quadratic equation of the form ax² + bx + c = 0

    Equation Coefficients

    Enter the coefficients a, b, and c for ax² + bx + c = 0

    1x² + 5x + 6 = 0

    Solution

    Enter coefficients and solve to see the step-by-step roots.

    Quadratic Equation Solver: Find Roots Instantly

    Welcome to the Quadratic Equation Solver, a powerful algebra calculator designed to find the exact roots of any second-degree polynomial equation. Whether you are solving for x-intercepts in a high school math class or computing parabolic trajectories in physics, this tool completely automates the Quadratic Formula. By simply inputting your a, b, and c coefficients, our engine evaluates the discriminant and traces out the exact step-by-step arithmetic to reach your real or complex roots.

    The Quadratic Formula

    Standard Form: ax² + bx + c = 0

    x =
    -b ± √(b² - 4ac)2a

    The Fundamental Theorem of Algebra guarantees that every quadratic equation has exactly two roots. These roots can be two unique real numbers, one repeated real number (a double root), or a conjugate pair of complex numbers involving i.

    Understanding the Discriminant (Δ)

    The expression tucked inside the square root of the formula, b² - 4ac, is known as the Discriminant (denoted by Δ). It acts as an indicator, instantly revealing the specific nature of the roots without having to solve the entire equation:

    • Δ > 0 (Positive)

      Two distinct real roots. The parabola intercepts the x-axis at two completely different coordinates.

    • Δ = 0 (Zero)

      One real root. The parabola perfectly grazes the x-axis with its vertex, creating a single repeated solution.

    • Δ < 0 (Negative)

      Two complex roots. The parabola never touches the x-axis, resulting in imaginary numbers (i = √-1).

    Example Calculation

    Solving: 2x² - 4x - 6 = 0

    Coefficients: a = 2, b = -4, c = -6

    • Compute the Discriminant: Δ = (-4)² - 4(2)(-6) = 16 - (-48) = 64.
    • Since Δ is positive, expect two real roots. √64 = 8.
    • Root 1: ( -(-4) + 8 ) / (2*2) = (4 + 8) / 4 = 12 / 4 = 3
    • Root 2: ( -(-4) - 8 ) / (2*2) = (4 - 8) / 4 = -4 / 4 = -1

    Result: x = 3, x = -1

    Academic & Scientific References

    For further understanding and validation of the formulas used above, we recommend exploring these authoritative resources:

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