The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

Year 13 Maths Help Thread

Scroll to see replies

Reply 260
Avatar for Palette
Palette
OP
14
When I asked somebody on TSR whether I should learn FP2-FP3 and M3-M4 over the summer, he said that there isn't much point. Only in the past week did I understand what he meant. I will now concentrate on improving depth (on C1-C4) rather than breadth.
If you're asked to find the stationary point (sp) of f(x) then f(x-2) is there an easier way to find the sp for f(x-2)? (instead of subbing in x-2 then differentiating etc.)
Original post by kiiten
If you're asked to find the stationary point (sp) of f(x) then f(x-2) is there an easier way to find the sp for f(x-2)? (instead of subbing in x-2 then differentiating etc.)


Of course. f(x-2) is a translation by vector [2,0] from f(x).
Original post by Palette
When I asked somebody on TSR whether I should learn FP2-FP3 and M3-M4 over the summer, he said that there isn't much point. Only in the past week did I understand what he meant. I will now concentrate on improving depth (on C1-C4) rather than breadth.


That to me still doesn't sound like a great idea. You need to ask yourself what particular topics you want/need to challenge yourself on in C1-C4 if you even need to, or look at whatever it is you're trying to work towards (eg STEP or a university course that requires some areas in particular from FP2 and FP3 eg matrix algebra, taylor series) and pick out those ones rather than blindly going off in depth into C1-C4. That is how I would approach it anyway (understanding what exactly it is that needs work on).

Original post by kiiten
If you're asked to find the stationary point (sp) of f(x) then f(x-2) is there an easier way to find the sp for f(x-2)? (instead of subbing in x-2 then differentiating etc.)


Think about it with a graph to reach your answer.
Am i missing something? I keep getting the wrong answer :3

Posted from TSR Mobile
1470675062957.jpg41.7KB
1470675096609.jpg35.8KB
Original post by kiiten
Am i missing something? I keep getting the wrong answer :3

Posted from TSR Mobile


What's the actual right answer? x=1?
Original post by kiiten
Am i missing something? I keep getting the wrong answer :3

Posted from TSR Mobile


You've inadvertently uploaded your image in the wrong orientation. It's annoying how computers do that but mystifying how they would actually be able to fix it. But reading stuff sideways is not fun. Please try rotating the images on your computer or if it's on your tablet/phone, figure out which way you hold the camera to get the right orientation.
(edited 7 years ago)
Original post by SeanFM
You've inadvertently uploaded your image in the wrong orientation. It's annoying how computers do that but mystifying how they would actually be able to do it. But reading stuff sideways is not fun. Please try rotating the images on your computer or if it's on your tablet/phone, figure out which way you hold the camera to get the right orientation.


Agreed. My neck feels abused.
Original post by RDKGames
What's the actual right answer? x=1?


correct answer is 3+ sqrt 13
Rotated image :smile:

Posted from TSR Mobile
1470681154034.jpg45.5KB
1470681161643.jpg35.9KB
Original post by kiiten
correct answer is 3+ sqrt 13


In that case I'm correct, I was a bit hesitant to go forth with such an unrealistic answer applied to a real-life scenario.

Anyway,

You should not take the length of the path to be 2m, it simply does not make sense, it doesn't tell you this anywhere so I'm not sure where you pulled it from. The correct length would be 2x+2.

Here is the diagram showing so:
Original post by RDKGames
In that case I'm correct, I was a bit hesitant to go forth with such an unrealistic answer applied to a real-life scenario.

Anyway,

You should not take the length of the path to be 2m, it simply does not make sense, it doesn't tell you this anywhere so I'm not sure where you pulled it from. The correct length would be 2x+2.

Here is the diagram showing so:


How do you know its 2x +2? i thought it would be 2 because the width is 1 (the length of the middle part is twice the width).
Original post by kiiten
How do you know its 2x +2? i thought it would be 2 because the width is 1 (the length of the middle part is twice the width).


Whoops forgot to attach the diagram; it should explain it. Yes the WIDTH is 1, doesn't mean that it is doubled for the length.

"(the length of the middle part is twice the width)" that's only for the lawn.... which is separate...
asdas.PNG

Edit: Forgive my mouse writing skills.
(edited 7 years ago)
Original post by kiiten
How do you know its 2x +2? i thought it would be 2 because the width is 1 (the length of the middle part is twice the width).


Also if you think about, if the length was 2m, what the hell would happen to the path if x keeps increasing? It would be completely destroyed, covered by the lawn and your local city council would make your pay for it. Be careful with maths.
Original post by RDKGames
Whoops forgot to attach the diagram; it should explain it. Yes the WIDTH is 1, doesn't mean that it is doubled for the length.

"(the length of the middle part is twice the width)" that's only for the lawn.... which is separate...
asdas.PNG

Edit: Forgive my mouse writing skills.


The width of the path is 1 but how do you know the length after the lawn is also 1? - if that makes any sense
Original post by kiiten
The width of the path is 1 but how do you know the length after the lawn is also 1? - if that makes any sense


Because that's still the width of the path...
Capture.PNG
(edited 7 years ago)
Original post by RDKGames
Because that's still the width of the path...
Capture.PNG

Ohhh i misread the question: i thought the width of the larger rectangle was 1 (thats why i got it wrong)
Original post by kiiten
Ohhh i misread the question: i thought the width of the larger rectangle was 1 (thats why i got it wrong)


No problem, rookie mistake. :wink:
Original post by RDKGames
No problem, rookie mistake. :wink:


Haha thanks for your help :smile:
Original post by RDKGames
No problem, rookie mistake. :wink:


Now i got 3 + sqrt 17 instead of 3 + sqrt 13??? :s-smilie:

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you