An airplane flies with a velocity of 750. kilometers per hour, 30.0 o south of east. What is the magnitude of the eastward component of the plane's velocity?
2 Answers

draw the vector on an x,y grid
call pos x east and pos y north
so the vector will be 30 deg below the x axis
from the end of the vector draw perpendiculars to the x and y axes
now use trig to find the length of the x part of the rectangle you have drawn
I have a calculator where I can enter r,theta and punch a button to get x,y and get a value close to 650

Angle x is relative to due east
Vx=Vo(cos x)
Vx= (750.0 km/hr)(cos30)
Vx=649.52 km/hr