conics (is the devil) (1 Viewer)

[dawso]

it may be the devil, although this question has to be too simple??

last year's hsc paper, question 4 (C) (ii)

(for those without access to the paper....it is just an ellipse in standard form.....chord of contact drawn and the poiint from which the tangents have been drawn has been shifted to lie on the x axis on the directrix....then it says what is the ratio of ps:st...where p is the point, s is focus (on chord of contact) and t is the point form which tangents have come from....)

is it sufficient to simply say the ratio is e (focus directrix definition and same x values.....)

or should it need 2 be algebra bashed....

 

[KFunk]

Ussually it's a given that conics = le bash algebraique but I don't see why you shouldn't be able to use conic definitions in your proof. I'd probably go with the bash (which isn't too bad, relatively speaking) in order to make sure I got the marks. Btw:

 

[dawso]

lol, i was about 2 call u a sell out for making such a creation and then supporting conics, id like 2 remind all future 4unit students of the joy provided by kfunk's wonderful masterpeice.....in fact, this is the foto i just took on my phone of my 4unit folder

 

[KFunk]

I felt that the up and coming 2006 young'ns had to be warned. I attached an image this time so that they can recognise satan when he starts to rise out of the page. (P.S. - you have the world's best 4U folder)

 

[Tincat]

Ah, people who share my pain!

I think I shall sell my soul to conics in exchange for actually being able to do the conics stuff in the paper on Monday...

P.S. Very nice artwork!

 

[Dumsum]

The only satanic part about conics is the locus stuff. There's always marks to be had with the "show that the tangent to the ellipse at the point P has equation blah" questions.

 

[underthebridge]

Yeh that stuff is ok, and most of the algebra bashing is alright. I don't like prooving the reflection property, and the equation of chord in parametric form of a hyperbola really sucks.

Other crap stuff is usually area stuff.

 

[Sepulchres]

I find the parametric bits much easier and logical than the algebraic workings. And unfortunaely, BOS favours the algebraic method much more than the parametric. =\