Polar form of a complex number (1 Viewer)

[mazza_728]

Hey guys,
i took ur advice and ive started the topic by myself.. im going ok and i understand everything so far to do with complex numbers except this:
when you are expressing a cartesian equation in modulus argument form e.g. z= -1 -i
i understand all the algebra involved except for why do we only express arg where -(pie)< theta <(pie)? and also when implementing argz=theta +/- 2n(pie) there is a funny symbol that looks like a curvy "E" that says, n E J!?!?! what does that mean??
can anyone help?
please
thanks xoxo

 

[Rorix]

From -pi to pi is the principle argument, the most basic version. The definition of the argument is the angle the vector makes with the positive direction of the x axis, so clearly angles outside the -pi to pi range will co-orespond to an angle in the range. So in short, it's just a more simple version, similar to 6/4 = 3/2.

The curvy E and J means that n is an integer. If I recall correctly, the e means something like "belongs to" and the J means integer. Other common ones are C for complex and R for real.

 

[spice girl]

never seen J before....it must be dodgy

usually its n e Z (Z is the set of all integers). If so, the +/- is redundant because Z includes negative integers anyway.

more appropriately n e N (N is the set of positive (or non-negative?) integers ("natural numbers"))

 

[Rorix]

J is actually rather common...

 

[:: ck ::]

the E means element of

 

[mazza_728]

so ur saying n is an element of an integer.. is that just that n is an integer?

 

[Constip8edSkunk]

think of all the integers as a set, n is an element of that set, ie. n is an interger

 

[KeypadSDM]

Z is the set of integers.
:. n E Z
n 'is a member of' 'the set of integers'

 

[mazza_728]

Ok sweet.thanks guys xoxo