Complex numbers

Could you post your working out of what you've tried so far?

Alright cool

Remember these are literally just expressions like a, b and c themselves. Get the expression of (A) + i(B) by carrying out the subtractions given, Then remember the formula of r? Using pythagoras's theorem?

And remember how to work out theta? Just plot those as normal

Sorry im slightly confused.

Is b-a =(root 3 -2)+i?
|b-a|= root 8. Hm idk

Sorry im slightly confused.

Is b-a =(root 3 -2)+i?
|b-a|= root 8. Hm idk

They want you to draw an argand diagram, plot the complex numbers and think of triangles. Does that help in anyway?

E.g: draw a and b, then b-a is the line connecting the endpoint of a to the endpoint of b

One thing that's confusing me is how they say use it to express it exactly in the form re^itheta. How does that work? Shouldn't it be done by calculation?

Haven't worked through it myself, but it might be easier to find r and the theta using geometry methods (soh cah toa/cosine/sine rule) instead of manual calculation.

Hmm fair enough. Just that they're not very nice values if you want to give them exactly

Hmm, you're right, that gives you horrible 'exact' answers