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General Thoughts: Mathematics Extension 2 (2 Viewers)

jonathanrsh

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1/z is the conjugate of z, no?

so l 1+1/z l = l 1+z-iy l = sqrt([1+z]^2 + [y]^2)

Square both sides, and you get a circle...
 

silence--

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mod (1+(1/z))<=1
mod (z+1/z)<=1
mod(z+1)<=mod(z)

let z = x+ iy and simplify

x =<-1/2

that should be right according to wolfram :L

(i think i shaded the wrong region lol. can't remember. FFUUUU)
 

nichorowitz

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anyone else think there was a mistake in the test?
in 5ai i swear they fucked up resolving of vectors
they used theta to obtain there result instead of 90 - theta and hence sin would become cos etc
i ended up just using theta to get there result but i swear they did it wrong
 

rawrence

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anyone else think there was a mistake in the test?
in 5ai i swear they fucked up resolving of vectors
they used theta to obtain there result instead of 90 - theta and hence sin would become cos etc
i ended up just using theta to get there result but i swear they did it wrong
I wasted an entire page using 90-theta only to realise my answer didn't match

So i used theta.
 

silence--

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^also yeah, wtf. that confused the hell out of me. then just went with what they had.
 

timting95

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anyone else think there was a mistake in the test?
in 5ai i swear they fucked up resolving of vectors
they used theta to obtain there result instead of 90 - theta and hence sin would become cos etc
i ended up just using theta to get there result but i swear they did it wrong
I think i i remember correctly it had theta for both angles at the bottom and the top so using alternate angles it gave you the same result....it was different
 

khfreakau

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I thought the paper was challenging. Q7 was a massive joke haha. Also q6 resisted integration was just dicks for 3 marks. I loved when I got the integration reduction in q8 haha. anyone else find q4/5 a bit harder than normal? Hmmmm.
Sent from my GT-I9100 using Tapatalk
 

tomdoml

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Can't assume the string was a tangent to the sphere, have to take the angle from the normal at the centre of the sphere to get theta. Dw still didnt figure it out till after and I stuffed the exam real bad :S
 

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