General Thoughts: Mathematics Extension 2 (5 Viewers)

[jonathanrsh]

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...

 

[michaeljennings]

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...

no 1/z where z=x+iy is not the same as the conjugate of z which is x-iy

 

[HyperComplexxx]

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...

i dont think 1/z = x + iy

 

[rawrence]

wait wtf is this 7a(i)?

Where's part i :|

 

[silence--]

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]

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

 

[apollo1]

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...

thats only if the complex number lies on the unit circle.

 

[rawrence]

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--]

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

 

[apollo1]

yeah i just used wat they had.

 

[ball00n]

wait wtf is this 7a(i)?

Where's part i :|

sorry I meant just 7a) the volume question - what did you guys get?

 

[timting95]

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

 

[HyperComplexxx]

Yea at 5ai, i was like how what where when i was using 90-theta, ended up using what they had

 

[michaeljennings]

sorry I meant just 7a) the volume question - what did you guys get?

2pi - (pi^2)/2 Just realised I got this question wrong..

 

[someguy10]

sorry I meant just 7a) the volume question - what did you guys get?

Pi ln2 + pi^2/2 - 2pi using radius (1-x) and height f(x) I think

 

[khfreakau]

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]

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

 

[rawrence]

Pi ln2 + pi^2/2 - 2pi using radius (1-x) and height f(x) I think

I got this. A = 2pi(1-x).f(x)

 

[HyperComplexxx]

Pi ln2 + pi^2/2 - 2pi using radius (1-x) and height f(x) I think

i got the same as you but i didnt multiply the pi in :L

 

[muzeikchun852]

Pi ln2 + pi^2/2 - 2pi using radius (1-x) and height f(x) I think

I think i got this as well.