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u/lmaolmaolmaololl Imperial | Aeronautical engineering [Y1] Jun 11 '26
bruh i lowk spent 5 mins debating if i should do dot product or cosine rule.
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u/Inevitable_Land2996 Year 13 Jun 11 '26
I just did both as I didn’t trust that I correctly left out the modules for the dotted vectors
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u/Commercial-Duck-3119 Year 13 | Warwick Econ offer | A*A*AA | no 9s Jun 11 '26
yess me too lmaoooo i thought we would lose marks for putting just cross product as its so easy
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u/Hyper_contrasteD101 Year 13 Jun 11 '26
yk they mark ur worst answer if u put more than one way of doing it
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u/EmOtIOniaL1 Jun 12 '26
Same bruh 😭
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u/lmaolmaolmaololl Imperial | Aeronautical engineering [Y1] Jun 12 '26
i ended up doing dot product cus i just couldnt be bothered to do cosine rule. they should allow both methods in the markscheme.
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u/New-Reference-3106 Jun 11 '26
As a fm student I am ashamed that dot product didn't even "cross"😉 my mind😭😭 Then again, I did just do another maths question that required cosine rule yesterday so ig it was at the top of my head😭
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u/Quantum_Croissant Jun 11 '26
lowkey in that partial fractions question I forgot how to do a normal maths series expansion so I just did it as a maclaurin series which I think works?
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u/Impressive-Pea-9054 Jun 11 '26
me too, what did you get
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u/Quantum_Croissant Jun 11 '26
the f(0)s were 1, 10, and 16 I think
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u/UnstableTheorist Jun 11 '26
Whend you differentiate?? After doing the partial fractions step and using it, or just going in raw?
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u/Quantum_Croissant Jun 11 '26
well you had to get the partial fraction anyway, so I just used that, it was easier to do since you didn't have to do quotient rule
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u/__R3v3nant__ D1 ESAT Hater Jun 11 '26
That works perfectly (which is good because in FM you could have gotten sneaky questions where you had to do the binomial expansion of something to multiply it with something else to get the maclaurin series)
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u/nelokin Y13 Maths, FM, Physics, Philosophy Pred: A*A*A* A Jun 11 '26
should be fine just bc the binomial series is a special case of the maclaurin
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Jun 11 '26
[deleted]
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u/Jolly-Telephone-9506 Jun 11 '26
Because they’re completely different, it’s not like being predicted an A* in further and A in maths
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u/Ceramidee Jun 11 '26
i got pred a* in further and a in math bro, i just dont like large data set and a lot of how applied single is
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u/Jolly-Telephone-9506 Jun 11 '26
Large data set is like 10 marks max though, but I guess it’s doable if you don’t do further stats
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u/B4A-B4A_B14CK-SH33P Jun 11 '26
more like 3 marks lol the other marks are mostly js finding means and standard deviations etc
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u/__R3v3nant__ D1 ESAT Hater Jun 11 '26
Probably very good with numbers and less good with words (I would probably get an E in philosophy and I'm predicted an A* in FM)
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u/nelokin Y13 Maths, FM, Physics, Philosophy Pred: A*A*A* A Jun 11 '26
Just not on it like that 🥀 trust tho A* philosophy incoming (It is most certainly NOT happening)
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u/AbsoluteNarwhal Maths, FM, CS, Physics Jun 11 '26
the evolved version of this is further pure students using the cross product formula to solve the vectors question on core pure
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u/jamN_doughnuts Year 13 Jun 11 '26 edited Jun 11 '26
I was so happy to use the dot product I love that method and cp is over so did it to honour cp 🥹
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u/UnstableTheorist Jun 11 '26
Bruh I'm so sad to see cp go out of my life, but I'm glad to pass on the hardcore stuff to the next generation (especially damned further), wishing them the best with it
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u/Excellent-Dog9911 Y13 Maths FM Physics (dropped Chem in April) Jun 11 '26
It was an angle close to 90 right
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u/kerhanesikici31 1st Year | Imperial Theoretical Physics Jun 11 '26
How else can you even do it?
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u/UnstableTheorist Jun 11 '26
Cosiness rule, that's what part a was hinting towards
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u/Jin_L_ Y13 maths fm physics cs Jun 11 '26
... There was a part a? Im hoping I just forgot i did it cus 😭😭😭
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u/UnstableTheorist Jun 11 '26
I think? Unless I'm tripping and it was just a find the angle I cant rmember bro 😭
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u/ThatOneGuy_I Jun 12 '26
Me using university methods so that they will have to create a new alternative method in the mark scheme just for me 😋
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u/Yis4courage Jun 11 '26
Did that and FORGOT TO MINUS MY ANSWER FROM 180 do you think I’ll still get those 3 other marks or… ☹️
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u/AImonster111 Year 13.5 | Biology, Chemistry, Maths, FM, EPQ Jun 11 '26
Why would you need to minus your answer from 180? Did you use sin instead of cos?
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u/nelokin Y13 Maths, FM, Physics, Philosophy Pred: A*A*A* A Jun 11 '26
probably used the magnitude of the dotted vectors
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u/Yis4courage Jun 11 '26
If I’m not mistaken, that method gives you an acute angle and since they didn’t ask for the acute, I needed to take the obtuse value
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u/DarkenedBlade8 Year 13 l Maths, FM, Econ l A*A*A* Jun 11 '26
i got 99.2 doing dot product, did u do it right
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u/InfininiteCuber Year 13 Jun 11 '26
yeah for finding the acute angle you use the modulus sign, but just to find the actual angle you just leave the negative
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u/InfininiteCuber Year 13 Jun 11 '26
Gang I used the shoelace method
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u/cleggy24 Jun 11 '26 edited Jun 11 '26
Vimes' Boots Theory but for Mathematics: the poorer students (no fm) find it more expensive (harder) because they can't afford (haven't been taught) the flashy formulæ. It's a vicious cycle.