### Cubic Equation

The formula **ax ^{3} + bx^{2} + cx + d = 0** is called the cubic equation, i.e. an
equation that has into its terms one variable of the third degree.

**If a = 0**, the equation is not cubic.

**If d = 0**, the equation has a root equal to zero and becomes a quadratic when dividing all the terms by x.

The cubic equations can have real roots and imaginary (complex numbers). The imaginary part is shown, beginning with the letter

**i**. Imaginary numbers, even though its name exist in many applications such as aerodynamics, electronics, electricity, etc.

The discriminant tells you the nature of the roots :

i - If more than zero, the equation has only one real root;

ii - If less than zero, the equation has all real roots ;

iii - If zero, the equation has real roots and all equal.

Enter data for the coefficients

**a**,

**b**,

**c**y

**d**. For positive numbers, the positive sign is dispensed.

To separate decimal place, use the decimal point. E.g. 15,151.47; enter 15151.47; The results will be displayed automatically after click on

**"Calculate"**.

### Related topics

Percent of a number Percent of a total Accumulated total by a percentage Percentage of two numbers Arithmetic mean Geometric mean Harmonic mean Quadratic mean Weighted mean Weighted geometric mean Weighted harmonic mean Standard Deviation Correlation Coefficient Simple Linear Regression Quadratic equation Cubic equation solver Nth root solver Nth Power of a number Logarithm & antilogarithm solver Trigonometric Functions Inverse Trigonometric Functions Directly proportional division Inversely proportional division Determinant matix 3 by 3 Linear equations in two variables Linear equations in three variables Rule of three - Direct proportion Rule of three - Inverse proportion Compound Rule of three Restaurant - checking the bill