Establish associative law of multiplication

[kathrynag]

Homework Statement

Establish associative law of multiplication by considering absolute values and arguments.
z1(z2z3)=(z1z2)z3

Homework Equations

The Attempt at a Solution

I think I need to use r(costheta +isintheta)
r1(costheta1+isintheta1)[r2r3(costheta2+isintheta2)(costheta3+isintheta3)]=
Is this just a bunch of multiplying out and showing it's the same?

 

[Dick]

Yes. The magnitudes multiply and the arguments add. Both operations are associative.

 

[kathrynag]

Ok, I think I see.