Equation

[amathproblemthatneedsolve]

I want to know what the equation is to set the distance between the upper and lower curves of a parabola. e,g finding where the height is 1m. between the upper and lower curve.

The equation is in the form [MATH]y^2=4ax [/MATH]Hopefully this makes sense.

 

[Dr.Peterson]

I want to know what the equation is to set the distance between the upper and lower curves of a parabola. e,g finding where the height is 1m. between the upper and lower curve.

Hopefully this makes sense.

A parabola is one curve; there is no upper and lower curve.

Please give a specific example, ideally a picture and the equation of your parabola, to show what you are asking.

 

[amathproblemthatneedsolve]

n the to say 1m and finding where that occurs.

 

[Dr.Peterson]

What is the equation of the parabola? You'll be using that to answer your question.

I presume you are asking for the value of x such that the difference between the two y values is 1, right?

 

[amathproblemthatneedsolve]

Don't worry solved it! I simply rearranged the equation as necessary.

 

[Deleted member 4993]

I want to know what the equation is to set the distance between the upper and lower curves of a parabola. e,g finding where the height is 1m. between the upper and lower curve.

The equation is in the form [MATH]y^2=4ax [/MATH]Hopefully this makes sense.

Since the curve is symmetric about x-axis, calculate the value of 'x' for y = 0.5 [using the equation y² = 4ax]

 

[JeffM]

I have worked with this student before. For some reason, his teachers insist that he use the equation y^2 = 4ax to describe parabolas even though such a form is neither a function nor a standard equation for parabolas. I have essentially answered this question for a specific case set by the student, but apparently I am not believed. What the student is looking for is 2y given arbitrary x and positive a.

The equation that would be useful for the problems he is working on (which involve a parabolic wall/roof) is y = ax^2 + c, where c is the maximum height of the roof, a is negative, and 2x equals the width of the building at ground level.

The whole thing is completely inane and arises from the fatuousness of his teacher in requiring a mathematical form that is entirely inappropriate to the problems being assigned.