Question

Help needed.
find the largest value the directional derivative of f(x,y,z)=xyz can have at the point (1,1,1)

Answer 1

I know you have to find the gradient

fx= yz, fy=xz, fz=xy

Answer 2

if you already have the gradient, using the formula fxa+fyb+fzc=Duf i got 3, i can't honestly say if that's right or not, my calc III final is on tuesday

Answer 3

fx, fy, fz, can be read as f sub x, f sub, and f sub z

Answer 4

I got 3 but i was not sure. My calc 3 is tomorrow evening

Answer 5

good luck, i know i'll need it