I am translating the question from another language so it might not be word to word with the original question.
assume x(s,t) and y(s,t) determined by these two functions:
The following function is defined H(x,y)=x2+y2-xy
find the partial derivative Kt(0,0) (the derivative of K in terms of t)
The Attempt at a Solution
first I wanted to solve the first two equation system in terms of x and y, but it didn't work.
tried also plugging them in to H, no success.
Would appreciate any help.