Tina, David and Ahmed share gold coins in the ratio of 2:4:4. David gets 80 more gold coins than Tina. How many gold coins did Ahmed get?

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