Question

By considering the product (2+i)(3+i) show that arctan(1/2) + arctan(1/3) = (pi/4)

Answer 1

Argument of (x+iy) is arctan (y/x).
so,Argument of (2+i) is ..... ?
Argument of (3+i) is ..... ?

Now, argument of product (a+ib)(c+id) is sum of arguments of individual terms,
so here, you need to find the product (2+i)(3+i) and calculate its argument.
it'll be =Argument of (2+i) +Argument of (3+i)
thats how you'll be able to prove what you wanted to.
tag me if you need further help.

Answer 2

@hartnn Thank you so much!

Answer 3

welcome ^_^