The user can resolve any biquadratic equation. To do this you have to introduce the value of the coefficients a, b and c. If the equation is in standard form, coefficient a is the number that multiplies to x to the power of four, coefficient b is the number that multiplies to x squared and coefficient c is the independent term.
To solve the biquadratic equation we do a change of variable that transform our fourth degree equation in a quadratic equation. We solve this second degree equation and finally we calculate our original variable.

The application explains each operation step by step.