- Homework Statement:
- see post
- Relevant Equations:
- ∇f⋅u= Direction vector
The gradient is < (2x-y), (-x+2y-1) >
at P(1,-1) the gradient is <3, -4>
Since ∇f⋅u= Direction vector, it seems that we should set the equation equal to the desired directional derivative.
< 3, -4 > ⋅ < a, b > = 4
I thought of making a list of possible combinations of a's and b's which satisfy this equation like so
corresponding direction vector
(for which there is no direction vector??)
< 4/√17 , 1/√17 >
But it seems that there are an infinite number of possible combinations. And the question is asking for all of them.
Thank you for your assistance.