General Thoughts: Mathematics Extension 1 (1 Viewer)

andrew29223

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What question did everyone find was the hardest?
Mighty Spiral! Uh the last bit of the binomial question in 14 was tricky for me but I'm sure many found it fine, i know a lot of my class mates couldnt get the very last question. I'm sure a lot of people (looking at the circle geo thread) assumed a straight line in their proof and will lose marks
 

Hotisgood5

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I used the fact that when two circles touches, the line through their centres passes through their point of contact. With that, all i have to proof is that the newly drawn line and QP intersects such that vertically opposite angles are equal.
 

lulwut

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I used the fact that when two circles touches, the line through their centres passes through their point of contact. With that, all i have to proof is that the newly drawn line and QP intersects such that vertically opposite angles are equal.
You can have vertically opposite angles be equal, but not necessarily drawn from the same lines right? Like just imagining the two triangles being skewed either way, and p is no longer colinear. I think you had to prove it using the angles to the tangent. I had no idea for this question during the exam LOL 0/3 for me ;_;
 

blinx96

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LOL i reckon i got around 38/70 (my 11th unit so idgaf)
But... anyone care to guess what this would align to as my exam mark :)
 

lulwut

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did anyone get around 20 s for the water droplet evaporating?
YES i got like 20.6.... seconds ish. cant remember exactly but around there. It felt a little funny because my expression for r was kinda weird though
 

Locus

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YES i got like 20.6.... seconds ish. cant remember exactly but around there. It felt a little funny because my expression for r was kinda weird though
Yah! i got like 20.68s from integrating the dV/dt equation and subbing in 'r' -> which i think was a constant in the formula
 

Locus

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Yah! i got like 20.68s from integrating the dV/dt equation and subbing in 'r' -> which i think was a constant in the formula
Yeah im starting to think its wrong --> people are getting around 60s with a different method --> maybe it was the assumption that r was a constant was wrong =/
 

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