hah im trully very SORRY, ok now i double checked.. so everything should be right ....
u, v, w are UNIT VECTORS. the angle between u and v is 25 degrees and the angle between vector v and w is 35 degrees.
find (u+w-3v). NOTE: vector u and w are on opposite sides of vector v.
I guess I am to assume that all three are in the same plane.
Arbitrarily take v to be in the x direction so is unit vector i
then
u = cos 25 i + sin 25 j
v = 1 i
w = cos 35 i - sin 35 j
then
u+w-3v = (cos 25+cos35-3)i +(sin 25-sin 35) j