This discussion is now closed.
Check out other Related discussions
- A level Maths Circle Question
- Please criticise my evaluation paragraph
- Psychology AQA a level - stress - tips and advice ? :)
- cubic one root proof
- Help with bioinformatics
- Wjec further maths unit 1 thoughts
- STEP Maths I, II, III 2001 Solutions
- AQA A Level Psychology Paper 1 (7182/1) - 17th May 2024 [Exam Chat]
- STEP Maths I, II, III 1993 Solutions
- robin's a levels study blog [the final slog]
- Discuss about restorative justices
- AQA A-level Psychology Paper 1 (7182/1) - 19th May 2023 [Exam Chat]
- All A's at Higher- Ask me anything!
- Edexcel A-level Psychology Paper 1 (9PS0 01) - 19th May 2023 [Exam Chat]
- Advice needed for student interested in mental health
- Isaac Senior Physics Challenge 2024
- A-level Maths Study Group 2022-2023
- OCR GCSE Latin Paper 1 (J282/01) - 14th May 2024 [Exam Chat]
- Differentiation help - points of inflection
- English langauge Gcse
Finding the Locus of a Point
This seems to be the main type of question I'm having trouble with in FP2.
I can usually work out the x and y coordinates of a specific point, but end up getting lost after that.
For example, a question from a Solomon Paper:
C is the rectangular hyperbola given by xy = c2, where c>0. P is the point (cp, c/p) and Q is the point (2cp, c/2p). P and Q both lie on C.
M is the mid-point of Q. Find, in Cartesian form, an equation of the locus of M as p varies.
So, in this example, I can work out the co-ordinates of M: (3pc/2, 3c/4p), but then I don't know what equation to sub into or what restrictions to place on it.
The answer given is xy = (3pc/2)(3c/4p) = 9c2/8. But I don't understand why the co-ordinates are subbed into the equation of the hyperbola, because M doesn't lie on C.
I can usually work out the x and y coordinates of a specific point, but end up getting lost after that.
For example, a question from a Solomon Paper:
C is the rectangular hyperbola given by xy = c2, where c>0. P is the point (cp, c/p) and Q is the point (2cp, c/2p). P and Q both lie on C.
M is the mid-point of Q. Find, in Cartesian form, an equation of the locus of M as p varies.
So, in this example, I can work out the co-ordinates of M: (3pc/2, 3c/4p), but then I don't know what equation to sub into or what restrictions to place on it.
The answer given is xy = (3pc/2)(3c/4p) = 9c2/8. But I don't understand why the co-ordinates are subbed into the equation of the hyperbola, because M doesn't lie on C.
Aaaaah, that makes sense.
THANK YOU!
THANK YOU!
You're welcome. 
I made a P5 revision thread last year, around exam time. Maybe it will be of help.
I made a P5 revision thread last year, around exam time. Maybe it will be of help.
Aww, thanks. dvs, what level of Maths are you actually studying?
dvs
Currently finishing up my first year at university.
Where you studying?
Related discussions
- A level Maths Circle Question
- Please criticise my evaluation paragraph
- Psychology AQA a level - stress - tips and advice ? :)
- cubic one root proof
- Help with bioinformatics
- Wjec further maths unit 1 thoughts
- STEP Maths I, II, III 2001 Solutions
- AQA A Level Psychology Paper 1 (7182/1) - 17th May 2024 [Exam Chat]
- STEP Maths I, II, III 1993 Solutions
- robin's a levels study blog [the final slog]
- Discuss about restorative justices
- AQA A-level Psychology Paper 1 (7182/1) - 19th May 2023 [Exam Chat]
- All A's at Higher- Ask me anything!
- Edexcel A-level Psychology Paper 1 (9PS0 01) - 19th May 2023 [Exam Chat]
- Advice needed for student interested in mental health
- Isaac Senior Physics Challenge 2024
- A-level Maths Study Group 2022-2023
- OCR GCSE Latin Paper 1 (J282/01) - 14th May 2024 [Exam Chat]
- Differentiation help - points of inflection
- English langauge Gcse
Latest
Trending
