General Thoughts: Mathematics Extension 1 (3 Viewers)

alexandred

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Thought the paper was reasonable overall, thought with the exception of part c q14 was very easy (if induction can't be too hard so as to not favour 4u students, why make it part of the tail end of the paper?). The circle geo in q13 was pretty good for 3u, though once you saw the construction it becomes quite clear - I expect it will catch a lot of people who essentially assume the result, though. Don't think I dropped any.
 

Killerb47

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Hoping for 60/70. Damn circle geo cost me. Enough for 94/95 aligned mark??
 

Hotisgood5

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Did anyone used the vertically opposite angles to prove the circle geometry question?
 

bangladesh

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I didn't think it was too bad but i do 4u so.. But i could imagine that it would be quite challenging for a 2u student.
overall wasn't too bad, hopig for 90% raw.
 

iPhone4

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Shit I went worse than expected. Got 64 in 2012 but hoping for 56-57 for this. Will that make an E4? 56/70?
 

alexandred

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Did anyone used the vertically opposite angles to prove the circle geometry question?
What vertically opposite angles were there? We don't know qpt are collinear so how did you do it? Curious to see your solution.
 

hayabusaboston

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What vertically opposite angles were there? We don't know qpt are collinear so how did you do it? Curious to see your solution.
It said the line AT intersects C2 at B, so A,T,B are collinear. COnstruct line QP, then angle QTB let be alpha, then since ATB straight line, angle QTA is 180-alpha. Now angle ATP is also alpha, from vertically opposite angled QTB and ATp. This means QTP must be a straight line, and so Q, T and P collinear.

Thats what I did. AM I WRONG?> lol
 

RealiseNothing

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It said the line AT intersects C2 at B, so A,T,B are collinear. COnstruct line QP, then angle QTB let be alpha, then since ATB straight line, angle QTA is 180-alpha. Now angle ATP is also alpha, from vertically opposite angled QTB and ATp. This means QTP must be a straight line, and so Q, T and P collinear.

Thats what I did. AM I WRONG?> lol
You're assuming QTP is a straight line, you can't do that.
 

alexandred

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It said the line AT intersects C2 at B, so A,T,B are collinear. COnstruct line QP, then angle QTB let be alpha, then since ATB straight line, angle QTA is 180-alpha. Now angle ATP is also alpha, from vertically opposite angled QTB and ATp. This means QTP must be a straight line, and so Q, T and P collinear.

Thats what I did. AM I WRONG?> lol
Your proof goes: qpt is a straight line => qpt collinear. You effectively assumed the result,
 

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