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    (Original post by Insight314)
    Do you mean deriving the diagonalised matrix using \textbf{D} = \textbf{P}^T\textbf{A}\textbf{P} ? If you are given eigenvalues, then you write them along the leading diagonal to get the diagonalised matrix, but if you are given eigenvectors then you form \textbf{P} which is the matrix with columns consisting of normalised eigenvectors. It depends on what the question is giving you. You can go either way since you can find eigenvalues using eigenvectors and vice versa using the characteristic equation for the matrix, but that would just waste unnecessary time.
    yea I just mean when have the eigenvalues can you just straight up write out D or is there some dumb rule where the examiners secretly want the derivation everytime without actually asking for it. But yeah Ill just write it down right away then. I think its one of those stupid things my teacher used to do everytime so I wasnt sure if it was necessary But thanks.
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    (Original post by EnglishMuon)
    yea I just mean when have the eigenvalues can you just straight up write out D or is there some dumb rule where the examiners secretly want the derivation everytime without actually asking for it. But yeah Ill just write it down right away then. I think its one of those stupid things my teacher used to do everytime so I wasnt sure if it was necessary But thanks.
    Sorry, I am confused. What derivation are you talking about? If eigenvectors are given, you use \textbf{D} = \textbf{P}^T\textbf{A}\textbf{P} and if eigenvalues are given then you just write them down as you are telling me about. You can do it the other way (turning eigenvalues into eigenvectors and then using the alternative method) but there is no point and it would take you way too long.
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    (Original post by Insight314)
    Sorry, I am confused. What derivation are you talking about? If eigenvectors are given, you use \textbf{D} = \textbf{P}^T\textbf{A}\textbf{P} and if eigenvalues are given then you just write them down as you are telling me about. You can do it the other way (turning eigenvalues into eigenvectors and then using the alternative method) but there is no point and it would take you way too long.
    Yea thats what I mean, when you pointlessly find the eigenvalues then find eigenvectors and do P^TAP. Cus everyone I know doing the exam does that everytime but it seems like a massive time waste XD
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    (Original post by EnglishMuon)
    Yea thats what I mean, when you pointlessly find the eigenvalues then find eigenvectors and do P^TAP. Cus everyone I know doing the exam does that everytime but it seems like a massive time waste XD
    Yeah, that's not needed. You can literally just place them on the leading diagonal, like you were talking about.
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    (Original post by Insight314)
    Yeah, that's not needed. You can literally just place them on the leading diagonal, like you were talking about.
    Thanks, thats good! Also i looked a little into the "...with physics" course last year but cant remember what the major differences are aside from not doing the numbers and sets part. Is the extra stuff just more mechanics/relativity stuff?
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    (Original post by EnglishMuon)
    Thanks, thats good! Also i looked a little into the "...with physics" course last year but cant remember what the major differences are aside from not doing the numbers and sets part. Is the extra stuff just more mechanics/relativity stuff?
    Have you taken a look at this - https://www.maths.cam.ac.uk/system/files/text_1.pdf ?

    You replace D&R and N&S for first year Physics NatSci courses. Here is more detail on which are replaced, and which ones you are doing from the Physics part:

    "The Mathematics with Physics option consists of courses given by the Faculty of Mathematics,which provide about three-quarters of the total workload, and courses given by the Physics department, including practical work, which provide the remaining quarter of the workload. The physics lectures provide a series of short courses on Dynamics,Rotational Mechanics and Special Relativity, Oscillating Systems, Waves and Quantum Waves, and Gravitational and Electromagnetic Fields. (These are the same as those in the first-year Physics component of the Natural Science Tripos.) The mathematical lectures are on Vectors and Matrices, Groups, Differential Equations, Vector Calculus,Analysis and Probability. There is no clash in the timetabling of the options, so that you can attend the lectures for both the Mathematics with Physics option and the Pure and Applied Mathematics option."
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    (Original post by EnglishMuon)
    Thanks, thats good! Also i looked a little into the "...with physics" course last year but cant remember what the major differences are aside from not doing the numbers and sets part. Is the extra stuff just more mechanics/relativity stuff?
    How did you find it?




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    FRREEEEEEWDDOOOOOOMMMM


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    (Original post by drandy76)
    FRREEEEEEWDDOOOOOOMMMM


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    No Physics tomorrow?


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    Anyone else here do the FP2 (MEI) exam this morning? It was horrendous honestly never had a harder A level exam
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    (Original post by Insight314)
    How did you find it?




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    Ah it was good thanks. I know I made one small error on the sin5x/sinx integration as I got an extra root 3/2 from somewhere but quite confident with the rest. How about u?
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    (Original post by EnglishMuon)
    Ah it was good thanks. I know I made one small error on the sin5x/sinx integration as I got an extra root 3/2 from somewhere but quite confident with the rest. How about u?
    I found the whole paper pretty easy, finished it fast up to 8 c) and then spent about 30-40 minutes thinking how to tackle 8 c). At the end I got it, although I am not 100% sure I got all the marks, I still think it is 100UMS.

    Physics next!


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    (Original post by Insight314)
    I found the whole paper pretty easy, finished it fast up to 8 c) and then spent about 30-40 minutes thinking how to tackle 8 c). At the end I got it, although I am not 100% sure I got all the marks, I still think it is 100UMS.

    Physics next!


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    haha yes indeed! I literally finished in 35 minutes then spent ages checking. What mark do u normally need about to get full ums then?
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    (Original post by EnglishMuon)
    haha yes indeed! I literally finished in 35 minutes then spent ages checking. What mark do u normally need about to get full ums then?
    75 is full UMS. What do you mean?


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    (Original post by EnglishMuon)
    haha yes indeed! I literally finished in 35 minutes then spent ages checking. What mark do u normally need about to get full ums then?
    Last 2 years has been like 65/75 for 100 but this year it will be much higher as i heard it was easy.


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    (Original post by physicsmaths)
    Last 2 years has been like 65/75 for 100 but this year it will be much higher as i heard it was easy.


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    wow thats low. I mean it was a little easier than usual, but theres never anything too dire so hopefully thats good
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    Can anyone predict what my score is for STEP 3? Thought I might scrape a 1 at first, but lost hope upon hearing that ppl find this an easy paper...

    Q1: Part (i) and (iii). Start working on part (ii) using some substitutions, got weird terms in sec^x, didn't continue.

    Q2: full (i), for (ii) and (iii) the lines and points I found were not independent of p, rather expressed in terms of r and q, so probably wrong.

    Q4: full

    Q5: part (ii) and part (iv), feeble attempts at (i) and (iii), didn't manage to prove them

    Q6: First bit about z^n-1

    Q8: Successfully done first two part, for third part did a few substitutions such as h(1-x), h(1/x), but ended up failing to find h(x).

    What do you guys reckon my chance of getting in with S,1,2? with a high S in STEP 1, average-ish 1 in STEP 2 and (maybe?) a high 2 in STEP 3?
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    (Original post by kznil)
    What do you guys reckon my chance of getting in with S,1,2? with a high S in STEP 1, average-ish 1 in STEP 2 and (maybe?) a high 2 in STEP 3?
    14 + 8 + 20 + Q5 + 4 + 15 = 61 + Q5, should be a low 1. Even if not, you've got an excellent chance of getting in with those grades.
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    (Original post by ComputerMaths97)
    Anyone else here do the FP2 (MEI) exam this morning? It was horrendous honestly never had a harder A level exam
    I did. I actually did the question that was apparently the hardest (Q2) and the rest of it fine but I have doomed myself to failure by being a complete idiot on Q3 (goodbye 18 marks). FP2 has been my favourite paper all year and for some reason I just did an unbelievably obvious stupid thing (I spent 45 mins on it as well).

    Oh well, goodbye A* in FM - if I get rejected because of this and I still make my STEP I will just laugh.

    p.s. my mess up in q3 was equating (M-lambda(I))v = lambda*v i.e. finding eigenvector. I have found eigenvectors so many times before and never been so stupid.
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    (Original post by ComputerMaths97)
    Anyone else here do the FP2 (MEI) exam this morning? It was horrendous honestly never had a harder A level exam
    But yes, on another note it was indeed unlike any other A Level exam I have done before - it seemed as though in Q2 and even Q1 it took longer than normal and required a moment of realization.
 
 
 
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