Question

I need to find z1z2...
z1=1+2i, z2=-2-3i
I need to use arctan...to find theta..how to do it?

Answer 1

it would be tons easier just to multiply

Answer 2

can you show me how to get the arctan?

Answer 3

If you're asked to convert to polar form before solving and then bring the answer back to rectangular form, then you don't really need to evaluate the arctan when you get it.

Answer 4

but we are required to get arctan though, and I am converting it from a complex number

Answer 5

Then use a calculator.