• Best of luck to the class of 2024 for their HSC exams. You got this!
    Let us know your thoughts on the HSC exams here
  • YOU can help the next generation of students in the community!
    Share your trial papers and notes on our Notes & Resources page
MedVision ad

How would you sketch this? (1 Viewer)

xV1P3R

Member
Joined
Jan 1, 2007
Messages
199
Gender
Male
HSC
2010
I think you're mistaking it with arg[a] + arg = arg[ab]

So it's the other way around (products and sum)
 
K

khorne

Guest
It would work the same Arg(z +iz), but arg(z+iz) does not expand to arg(z) + arg(iz)
 

kr73114

Member
Joined
Aug 6, 2009
Messages
373
Gender
Male
HSC
2011
is that similar to arg(z-2/z+2)=pi/2
how would u do that?
 

Patato

New Member
Joined
Nov 5, 2009
Messages
27
Gender
Male
HSC
2011
arg(z-2/z+2) = pi/2 is a semi circle with centre 0,0 and radius 2 found using either circle geometry rules
 

Drongoski

Well-Known Member
Joined
Feb 22, 2009
Messages
4,255
Gender
Male
HSC
N/A
arg(z-2/z+2) = pi/2 is a semi circle with centre 0,0 and radius 2 found using either circle geometry rules
Is it then the upper semi-circle or lower or both?
 
Last edited:

Drongoski

Well-Known Member
Joined
Feb 22, 2009
Messages
4,255
Gender
Male
HSC
N/A
how do u know?
You can draw the circle centre origin radius 2. You take a convenient typical point z in the upper semicircle and see if arg(z-2) - arg(z+2) = pi/2 or - pi/2. Do the same for convenient typical point z on lower semi-circle.
 
Last edited:

Patato

New Member
Joined
Nov 5, 2009
Messages
27
Gender
Male
HSC
2011
you can break up arg(z-2/z+2) into arg(z-2) - arg(z+2), so sketch two vectors that intercept to make a right angle, (their args subtract to give pi/2), and you know from circle geometry that an angle at the circumference of a circle when subtended by the diameter of the circle will be a right angle, therefore you know its a circle, with its centre half way between the origin of the two intersecting vectors...so 0,0. but its a semi circle because if the vectors went into the negative half of the y axis, the arg would be negative if we are talking about the primary argument. id sketch it for you but im on a laptop and i cant stand the touch pad in paint
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
You can draw the circle cente origin radius 2. You take a convenient typical point z in the upper semicircle and see if arg(z-2) - arg(z+2) = pi/2 or - pi/2. Do the same for convenient typical point z on lower semi-circle.
Or deduce it from the external angle property of a triangle... (easier, I think).
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top