Brittany has a hoop. She wants to put tape around the edge of the hoop. How long does the tape have to be to cover the hoop completely?

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