cheers about to see whether the e4 is still in reach...
Maths Ext 2 Predictions/Thoughts (5 Viewers)
- Thread starter Anaya R
- Start date
Just note that the wolframalpha solution for 16c seems incorrect. I probably should delete it. Paradoxica's looks better.
about q13b) the integral one, if you did a trig sub and left limits in arccos(root whatever) and it came out as the right number i believe 136/5, do you reckon its still a viable full mark or was the other sub needed?
i reckon it is. i did trig sub as well but forgot to carry a factor of 243 out the front the whole time so i got the answer divided by 3^5. but it still works in the end. would i get a carried error here and lose 1 mark? in the end it said evaluate and it didnt specify the sub
yeah thats what im wondering, i really thought i stuffed up when seeing 243...
in the exam? why?
idk just didnt expect 243, kept with it cause time wise but i already accept a defeat when there is definite integrals i always evaluate wrong
if thats accepted thatd be really unfair. the correct way is to expand the rhs like a binomial (2+3)^nand show they dont match by contradiction. by the way for this question, is writing the assumption worth at least 1 mark?Alternative solution to 15d.
By Fermat's Last Theorem,for
Also,
Not sure if it would be accepted though.
Perfectly valid proof though.
i evaluated both of them wrong dw. first one i did what i just said, second one i did difference of two squares wrong.
really hoping e4 is lower then last year then it might be possible by the looks of these solutions
my estimate is 75 for e4. rui from atar notes said "This, however, has got to be the most draining MX2 paper I've done in a very long time. The only other time I recall of feeling so defeated was in 2018 or something where the chaotic Euclidean geometry question showed up" according to the raw marks database, in 2018, an e4 cutoff was exactly 72 raw but tbh i think more people did better in this exam than i originally thought so e4 might be higher like 75-77, possibly 80. a raw of 90 might then scale to a 95. would be amazing if it was closer to 2014 scaling, raw 90 scaled to a juicy 97.
yeah i think in the moment i thought it was a lot harder then looking back at it now, but still q16 and q15 proof topic, compared to last years proofs cant believe they got prove (a-b)^2>0
it was amgm inequality but awkwardly with a triangle?????? this years amgm inequalities i could do. but tbf the second one with a 6 in the denominator was too many marks. shoudlve been 2 marks because it wasnt that much working, just apply the formula a different way 3 times then add them.
yeah q15 was easier i agree, i didnt do it the way the mods on here did it, i let c=ab for memory but every worked out fine. q16 though literally didnt spend like anytime on the triangle inequality in study so when i saw it...
the morning of the exam i legit learnt it for the first time since last year. i got all of part a except for iii my reasoning was really dodgy. i got the root 3 part, you let b = (1 1 1) and a=(x y z)
watch us all stress for no reason and it ends up getting relegated to q10 of the mc and a simple q11 or 12 combination q. then projectile will take up all of 14. tbh i think de has really good potential for q14.
bro i saw it and instantly though, triangle inequality in 3d really? never seen that before maybe i just got really unlucky not every seeing it