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Online Quadratic Equation Calculator

Online Quadratic Equation Calculator

Solve quadratic equations quickly and accurately using our online quadratic equation calculator. Calculates real and complex roots based on the discriminant of the equation.

Equation 1x2 + 8x + 12 = 0
Solution x = -2 or -6

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What Is This Tool?

This calculator solves quadratic equations of the form ax² + bx + c = 0 using the quadratic formula. It determines the roots by computing the discriminant and provides both real and complex solutions with high precision.

How to Use This Tool?

  • Enter the coefficient values for a, b, and c in the respective input fields.
  • Ensure that coefficient a is not zero to form a valid quadratic equation.
  • Click the 'Calculate' button to solve the equation.
  • Review the displayed discriminant to understand the type of roots.
  • View the calculated solutions provided by the tool.

Key Features

  • Solves quadratic equations using the standard quadratic formula.
  • Determines the nature of roots based on the discriminant value.
  • Provides up to two real or two complex solutions accordingly.
  • Utilizes precise floating-point arithmetic for accuracy.
  • Simple, easy-to-use browser-based interface.

Examples

  • Solve 2x² - 4x - 6 = 0: Compute discriminant D = (-4)² - 4(2)(-6) = 64, then apply the formula x = (4 ± 8) / 4, resulting in solutions x₁ = 3 and x₂ = -1.

Common Use Cases

  • Students and educators solving algebra homework and teaching quadratic equations.
  • Engineers analyzing parabolic trajectories and optimization problems.
  • Scientists and programmers dealing with quadratic relationships in physics or data analysis.

Tips & Best Practices

  • Double-check that coefficient a is not zero before calculation.
  • Input numerical coefficients carefully to avoid errors.
  • Interpret the discriminant to understand whether solutions are real or complex.
  • Use the tool to verify manual calculations for accuracy.
  • Be aware of floating-point precision limitations with extremely large coefficients.

Limitations

  • Coefficient a must be non-zero for the equation to be quadratic.
  • Very large or small input values may lead to floating-point rounding errors.
  • Complex solutions are displayed numerically and not as symbolic expressions.

Frequently Asked Questions

What happens if the discriminant is negative?
When the discriminant is less than zero, the equation has two complex solutions which are shown numerically by the calculator.

Can this calculator handle any quadratic equation?
The calculator solves any quadratic equation where the coefficient a is not zero and coefficients are within floating-point precision limits.

How is the discriminant used in solving quadratics?
The discriminant determines the type and number of solutions: positive for two real roots, zero for one repeated real root, and negative for two complex roots.

Key Terminology

a
Coefficient of x² in the quadratic equation.
b
Coefficient of x in the quadratic equation.
c
Constant term in the quadratic equation.
Discriminant (D)
Value calculated as b² - 4ac that determines the nature of quadratic roots.
Roots (x)
Solutions of the quadratic equation found using the quadratic formula.

Quick Knowledge Check

What does a discriminant value of zero indicate about the roots?