Maths Extension 2 thoughts (2 Viewers)

leehuan

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I got (1/2)(rt(1/a^2 + 1/b^2)) for the area

Someone please tell me they got the same.
Just realised I lost a mark here...

For some reason I had PQ with |tantheta-sectheta| whereas the perpendicular distance |tantheta+sectheta|

Nvm I'm an idiot THEY WERE BOTH IN THE NUMERATOR LEE
 

knightus10

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Hated the conics question so much. One little mistake cost me the 5 marks in that question. Gahhhhh
 

knightus10

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By the way, what do you guys consider a good mark? Like i reckon 70 and above is great (scales to E4 i'm assuming). But everyone is saying this year was really easy, so do you think 70 is enough for an E4?
 

Thjv

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what did you guys get for the a^4 + B^4 + y^4 question? completely fkd that one up
Well since a, b and y are all roots of P(x), then
a^3 + ap + q = 0 ----- (1)
b^3 + bp + q = 0 ----- (2)
y^3 + yp + q = 0 -----(3)

a x (1) + b x (2) + y x (3)

a^4+b^4+y^4 + p(a^2+b^2+y^2) +3q(a+b+y) = 0

(This is all from memory. The polynomial that I wrote may not have been correct)
 

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