Quadratic function

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A quadratic graph that has two real answers.
A quadratic graph with two real answers and no complex answers. Other quadratic graph have no real answers and 2 complex answers.

In algebra, a Quadratic function is a function that contains an expression where its degree (the highest exponent it has) is 2, which means that it is quadratic (See etymology). Its single-variable standard form isː

f(x)=ax2+bx+c

Where a, b and c are all constants and a ≠ 0.

When such a function gets plotted on a graph where f(x)=y, a curve that extends infinitely called a parabola will appear.

When a quadratic function is set equal to zero, then it turns into a quadratic equation. The answers to the equation are where the function crosses the x-axis.

Etymology

The word quadratic comes from the Latin word quadrātum ("square"). This is because of the presence of a number (which isx2 in the standard form) that is the result of squaring its square root (x×x=x2).Template:Polynomials Template:Math-stub