First Focus

Or they can be, I don't want to say always.

The scaling factor was 1.

But where's the focus point?

And what we want to do is, we want to find out the coordinates of the focal points.

A conic with given directrix and focus, through a point

Select the first focus of the new ellipse...

Finally, say a known object is 300 m away.

Select the first focus of the new hyperbola...

Focal length

Focal

Focal Length

Focal blur

Focal point

Second Focus

Focal Length

Focal length

And this is f2.

And it's for focus.

Because this point right here, our vertex, is equidistant, it's 1 4 below our focus and it's 1 4 above our directrix.

Focal length of the lens

Well, we just used the distance formula.

So there's one point that just by looking at it we could say is going to be in our locus.

This is our first quiz.

There is an equation that governs all of this, and it looks about as follows

We have focused on the worst case scenario.

That's our directrix and it has the equation y is equal to k.

And what I need, in effect, is a focus.

Ellipse by Focuses Point

And now we should be able to use this information to figure out the actual coordinates of the focus and the directrix of what I would call the classic parabola, y is equal to x squared.

The walls of the egg then become impervious to other sperm so that only one sperm can get in, but that's not the focus of this video.

35mm equivalent focal length

That's this distance right there.

And that's what we set out to figure out in the beginning.

And you enter that space, and you feel like, Wow!

Requires great focus.

Just focus.

Bifocals.

Your focus,

It looks something like that.

Hyperbola by Focuses Point

So they intersect in exactly one place.

However, if I ask your minds to focus currently on Pakistan, and I ask you to think of the symbols and the leaders for democracy in Pakistan today, you'll be hard pressed to think beyond perhaps the assassination of Benazir Bhutto.

I'll call that well, we'll call that a focus because it will be a focus.

I want to focus on just one of them.