HSC Tips - Conics (1 Viewer)

[McLake]

Thread 3 in series ...

Tips for Conics:
- Don't learn formula, derive them on the spot (you are most likley going to be asked to do this any way)
- Do lots of practice question so that you familurise yourself with the types of questions asked.
- ALWAYS sketch the question as a visual aid.
- KNOW how to derive the equations/graphs from the defintions (things like PM = ePD) because some questions involve this.
- Many Q7/8 come from conics, be prepared for harder questions ...

EDIT:
- Most questions on conics are in sections. Even if you can't do one part attempt another ...

 

[freaking_out]

another golden tip that i found is that: whenever u r asked to "show" something, instead of working independently, always refer to the final answer that u r meant to derive and try to steer yourself towards it.

 

[Affinity]

- parametric form allows you to work witha single variable in trig form, cartesian form allows you to work with two variables satisfying a set of conditions. use parametric form if you are stuck.

- the sum of the roots of (x^2 + ax + b=0) is -a. You might not need to solve equations. Eg: Conic C intersects line L at 2 points, and you need to find the midpoint of the intersection.

- Algebra, Algebra and more practice on Algebra.

- Give the question a little thought before you start writing

 

[freaking_out]

use parametric form if you are stuck.

yeah, i think especially for those killer locus questions!!!

 

[Affinity]

for locus problems.. it might help if you know what it looks like before you start.

99% of the time you will get another conic(perhaps degenerate) that is a quadratic curve: ax^2 + bxy + cy^2 + dx + ey + f = 0

 

[freaking_out]

hey affinity, i c how ur good at conics, i wanna know how u came good at conics and what textbook did u use?

 

[Affinity]

All textbooks are good, My school uses Arnold/Arnold and the Coroneos supplement(this one is really nasty).

It's not that much of being smart, perseverance solves the question: don't stop when the mess seems to overwhelm you.

 

[aud]

Originally posted by Affinity
All textbooks are good, My school uses Arnold/Arnold and the Coroneos supplement(this one is really nasty).

It's not that much of being smart, perseverance solves the question: don't stop when the mess seems to overwhelm you.

Coroneos Supp is really nasty... we'll do everything from Fitz, and I can do Patel easily, but then we'll hit Coroneos, and we're like, ahhh...

 

[KeypadSDM]

Originally posted by aud
Coroneos Supp is really nasty... we'll do everything from Fitz, and I can do Patel easily, but then we'll hit Coroneos, and we're like, ahhh...

If you keep bashing, you'll eventually get it out. It may not be elegant, but you'll get there.

 

[freaking_out]

Originally posted by KeypadSDM
If you keep bashing, you'll eventually get it out. It may not be elegant, but you'll get there.

na, some of the conics questions (such as the one in catholic papers) are too hard, and involve too much tricks- such that u can never get them out!

 

[KeypadSDM]

Originally posted by freaking_out
na, some of the conics questions (such as the one in catholic papers) are too hard, and involve too much tricks- such that u can never get them out!

Well I'm glad I never did them.

 

[freaking_out]

Originally posted by KeypadSDM
Well I'm glad I never did them.

yep, and i'm hearing rumours that conics is gonna b taken out of the new 4u maths course...hence u would've noticed, that the conics questions for the past couple of years in the hsc, have been becomming easier.

 

[Affinity]

*prays so they're not gonna replace it with an extended response section*

 

[freaking_out]

Originally posted by Affinity
*prays so they're not gonna replace it with an extended response section*

haha- LoL...i don't think ya prayers r gonna b answered.

 

[Xayma]

Originally posted by freaking_out
haha- LoL...i don't think ya prayers r gonna b answered.

Well purely because I dont like the years below me *sacrafices a human to make it be replaced with extended response.

 

[paganinio]

It's not that much of being smart, perseverance solves the question: don't stop when the mess seems to overwhelm you.

according to my experience, when the mess seems to overwhelm you, it WILL really overwhelm you just several minutes later if you don't stop!

I gotta edit this post.

 

[:: ck ::]

altho this is the basis of conics.. many ppl who have asked questions here seem to forget the fact PS/PD = e ...

just keep it in ur mind as u do stuff... easiest way to prove PS + PS' = 2a ... ive seen this q posted SOO MANY TIMES here.. so yeah =)

 

[_ShiFTy_]

I've come across many questions that involve sums and products of roots. If you encounter any of these problems, the latter parts of the question will sometimes need you to plug the values of the sums/products in...

 

[x.Exhaust.x]

Thanks for the tips!

Are there any common proofs that appear readily in the same exam over and over again? For example, | PS + PS' | = 2a is one of them. What appeared in your exam that you encountered previously in a past paper? .

My tip is that many people neglect the reflection property, which is tested in the syllabus. My teacher didn't cover it in class, so make sure you go through it.

"It should be noted that locus problems on the ellipse are not included in the course" - 50 Exam Tips Excel. How come everyone here has been saying there are locus problems?

 

[Dumbledore]

Thanks for the tips!

Are there any common proofs that appear readily in the same exam over and over again? For example, | PS + PS' | = 2a is one of them. What appeared in your exam that you encountered previously in a past paper? .

My tip is that many people neglect the reflection property, which is tested in the syllabus. My teacher didn't cover it in class, so make sure you go through it.

"It should be noted that locus problems on the ellipse are not included in the course" - 50 Exam Tips Excel. How come everyone here has been saying there are locus problems?

there are no locus problems on ellipse's i'm not sure if there are any on general hyperbolas, but there are definitely some on the special hyperbolas