For which interval is the average rate of change of ex) negative?

An airplane is taking off headed due north with an air speed of 173 miles per hour at an angle of 18° relative to the horizontal. the wind is blowing with a velocity of 42 miles per hour at an angle of s47°e. find a vector that represents the resultant velocity of the plane relative to the point of takeoff. let i point east, j point north, and k point up.