Please Help with this complex number question!! (1 Viewer)

[umm what]

Can someone do (e) for me plzzz.
The question is wrong, its pie/2 instead of pei/4.
Like i know its vector addition but i dont know how to show they are equal.

THANKS A LOT!

 

[nightweaver066]

 

[Drongoski]

Can someone do (e) for me plzzz.
The question is wrong, its pie/2 instead of pei/4.
Like i know its vector addition but i dont know how to show they are equal.

THANKS A LOT!

You are right. the angle between z1 and z2 should be pi/2. The associated parallelogram is a rectangle - can be a square but not necessarily.

 

[Carrotsticks]

This question was posted before, and I remember Math Man gave a very detailed explanation regarding why it is pi/2 not pi/4.

 

[Aesytic]

i have a couple of questions about nightweaver's answer [our school just started complex numbers],
1. what does the arrow above |QP| and |OR| mean?
2. if there any other way to do this question? i would have done it this way too but is there an alternative to this?

 

[Drongoski]

This question was posted before, and I remember Math Man gave a very detailed explanation regarding why it is pi/2 not pi/4.

By geometry it's simple. |z1-z2| and |z1+z2| are the lengths of the 2 diagonals of the associated //gram. For the 2 diagonals to be equal, //gram must be a rectangle (can be a square, of course).

 

[Carrotsticks]

i have a couple of questions about nightweaver's answer [our school just started complex numbers],
1. what does the arrow above |QP| and |OR| mean?
2. if there any other way to do this question? i would have done it this way too but is there an alternative to this?

Arrows mean Vector. QP with an arrow on top means Vector QP = P - Q

 

[Drongoski]

i have a couple of questions about nightweaver's answer [our school just started complex numbers],
1. what does the arrow above |QP| and |OR| mean?
2. if there any other way to do this question? i would have done it this way too but is there an alternative to this?

The arrows indicates the vectors QP and OR. He is quite good in geometric vectors and has used that knowledge to good effect.

 

[SpiralFlex]

Magnitttuuuudeeeeeee!

 

[Aesytic]

so does that mean vectors PQ and QP are different?

 

[SpiralFlex]

Yes in terms of direction, but they haff eqwal magniiitudddesss!

 

[Carrotsticks]

so does that mean vectors PQ and QP are different?

They have the same magnitude etc, but just point in opposite directions.

 

[Carrotsticks]

Yes in terms of direction, but they haff eqwal magniiitudddesss!

Haha dunno if troll....

 

[SpiralFlex]

Haha dunno if troll....

Having a bit of fun during my ice-cream break

Try some:

 

[Aesytic]

i get it now, thanks guys!

 

[Rezen]

Just a small technical point but shouldn't the answer be + or - pi/2 ?