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How would you sketch this? (1 Viewer)

xV1P3R

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I think you're mistaking it with arg[a] + arg = arg[ab]

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

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

kr73114

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is that similar to arg(z-2/z+2)=pi/2
how would u do that?
 

Patato

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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

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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?
 
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Drongoski

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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.
 
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Patato

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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

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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).
 

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