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DigiCalcs

Quadratic Formula

로도 알려져 있음: Roots of Quadratic Equation

x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
x = (-b ± √(b² - 4ac)) / 2a

계산 내용

Finds the solutions (roots) of any quadratic equation ax² + bx + c = 0. The discriminant b² - 4ac determines the number of real solutions.

변수

상징이름설명
aCoefficient of x²Leading coefficient (must not be 0)
bCoefficient of xLinear coefficient
cConstantConstant term

유도

Derived by completing the square on ax² + bx + c = 0: divide by a, move c/a to the right, add (b/2a)² to both sides, factor the left as a perfect square, then take the square root.

실제 사례

1Discriminant = 25 - 24 = 1
2x = (5 ± 1) / 2
3x = 3 or x = 2
결과: x = 3, x = 2

일반적인 실수

Check that a ≠ 0 (otherwise it's linear, not quadratic)
If discriminant < 0, the roots are complex numbers

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#algebra#equations#polynomials

설정