two ships, one heading west and the other east, approach each other on parallel courses 8 nautical miles apart. Given that each ship is cruising at 20 nautical miles per hour, at what rate is the distance between them diminishing when the ships are 10 nautical miles apart?

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis