Parametric Equation Of A Parabola: Coordinates, Focus, Directrix

The parametric equation of a parabola relates to four key entities: coordinates, a parameter, a focus, and a directrix. It defines the x and y coordinates of points on the parabola in terms of a single parameter, ‘t’, which varies over a specified range. This parameterization allows for the exploration of the parabola’s shape and properties, including its focus, which is a fixed point, and its directrix, which is a fixed line parallel to the axis of symmetry.

The Best Structure for a Parametric Equation of a Parabola

A parabola is a conic section that is symmetric to a given axis. It can be described by a parametric equation, which is a pair of equations that express the coordinates of a point on the parabola in terms of a parameter.

The best structure for a parametric equation of a parabola is:

  • x = a + bt^2
  • y = c + dt

where:

  • a is the x-coordinate of the vertex of the parabola.
  • b is a constant that determines the horizontal stretch or compression of the parabola.
  • c is the y-coordinate of the vertex of the parabola.
  • d is a constant that determines the vertical stretch or compression of the parabola.
  • t is the parameter.

The parameter t can take on any real value. As t increases, the point (x, y) will move along the parabola.

Here is an example of a parametric equation of a parabola:

  • x = 1 + 2t^2
  • y = 3 – t^2

This equation describes a parabola with its vertex at the point (1, 3). The parabola opens up and down, and it is stretched horizontally by a factor of 2.

You can use parametric equations to graph parabolas. To graph a parabola using a parametric equation, you can:

  1. Choose a range of values for t.
  2. Substitute each value of t into the parametric equations to find the corresponding values of x and y.
  3. Plot the points (x, y) on a coordinate plane.

The resulting graph will be a parabola.

Question 1:

What is the concept of a parametric equation of a parabola?

Answer:

A parametric equation of a parabola expresses the coordinates of a point on the parabola in terms of a parameter. The parameter typically represents the distance along the axis of symmetry of the parabola from a fixed vertex.

Question 2:

How is the parametric equation of a vertical parabola derived?

Answer:

The parametric equation of a vertical parabola with vertex at (h, k) and axis of symmetry parallel to the y-axis can be derived using the following equations:

x = h + at
y = k + bt^2

where ‘a’ and ‘b’ are constants that determine the shape and orientation of the parabola.

Question 3:

What are the key features of the parametric equation of a horizontal parabola?

Answer:

The parametric equation of a horizontal parabola with vertex at (h, k) and axis of symmetry parallel to the x-axis has the following key features:

  • x = h + bt^2
  • y = k + at

where ‘a’ and ‘b’ are constants that determine the shape and orientation of the parabola.

Well, folks, we’ve covered the basics of parametric equations for parabolas. I hope you’ve enjoyed this little adventure into the world of mathematics. Remember, always remember, knowledge is power, and understanding the parametric equation of a parabola is just one more step on your journey to becoming a math superstar. Thanks for sticking with me, and be sure to drop by again. Who knows what other mathematical gems we can uncover together? Until next time, keep those calculators handy and your curiosity ignited!

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