parametrics :D (1 Viewer)

[jnney]

find the coordinates of three points on the parabola x^2 = 4y such that the normals through these three points pass through the point (-12, 15).

 

[SpiralFlex]

I got which should be correct, I will type my solution up.

Let's define a parameter for this equation of







At ,

The gradient of the tangent is

So the normal at that point must be





We know the equation of the normal passes through





By factor theorem,





Substitute that into our coordinates or parameters if you like and we get our coordinates of,

 

[hayabusaboston]

I got which should be correct, I will type my solution up.

Let's define a parameter for this equation of







At ,

The gradient of the tangent is

So the normal at that point must be





We know the equation of the normal passes through





By factor theorem,





Substitute that into our coordinates or parameters if you like and we get our coordinates of,

Niiiice spiral that's right.

 

[SpiralFlex]

Niiiice spiral that's right.

You've been following me around the whole day...

 

[hayabusaboston]

You've been following me around the whole day...

Eh, no, I do have better things to do my man. You appear on the threads I look at.

 

[SpiralFlex]

Eh, no, I do have better things to do my man. You appear on the threads I look at.

It's fine, I am use to this anyway.

Update: Jnney help count is now up to 31.

 

[SpiralFlex]

but are you used to people knowing your real identity ?

No cousin. I am not use to people knowing my identity.

 

[hayabusaboston]

It's fine, I am use to this anyway.

Update: Jnney help count is now up to 31.

So you've helped 31 times?

 

[SpiralFlex]

So you've helped 31 times?

Yes to the OP - Jnney.

 

[jnney]

Yes to the OP - Jnney.

How are you so sure? Feels like more than that, haha.

 

[SpiralFlex]

How are you so sure? Feels like more than that, haha.

You know how I store my pretty pictures I used to help people on my desktop? Eg. For (insert name here). I have counted them. Also I ask in return a cookie or a delicious human.