parabola graph calculator

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5
10
-5
-10
5
-5
x
y
D

Directrix

F
P
Q

d = 1.81

d = 1.81

click f or p or d and drag to move the image.

a function is a correspondence relationship in mathematics, from the non-empty number set a to the real number set b. simply put, a changes with b, and a is a function of b. to be precise, suppose x is a non-empty set, y is a non-empty number set, and f is a correspondence rule. if for each x in the correspondence rule f is said to be a function on x, denoted as y=f(x), and value range (the value range is a subset of y), x is called the independent variable, and y is called the dependent variable. it is also customary to say that y is a function of x. correspondence rules and domain are two elements of a function.

You can move the graph up-down, left-right if you hold down the "Shift" key and then drag the graph.

The parabola is defined as the locus of a point which moves so that it is always the same distance from a fixed point (called the focus) and a given line (called the directrix).

The focus of the parabola is at (0,p).

The directrix is the line y=−p.

The focal distance is |p| (Distance from the origin to the focus, and from the origin to the directrix. We take absolute value because distance is positive.)

The point (x, y) represents any point on the curve.

The distance d from any point (x, y) to the focus (0,p) is the same as the distance from (x, y) to the directrix.