Question

find by drawing and by calculation the resultant of two vectors 3units and 4units inclined to each other at 30°

Answer 1

if you let the vectors be

u = <4,0> and v = <3√3/2,3/2> then
u+v = <4+3√3/2,3/2>
|u+v|^2 = 25+12√3
the angle θ between u+v and v has
tanθ = 3/(8+3√3)