Dear Maple user(s), I have the next problem, hopefully you can help me: I have two Diff. Eqea. 1) diff(w,x,x) = -a*diff(w,y,y) 2) diff(w,x,x,x) = (a-2)*diff(w,x,y,y) a=constant Now, I need to know: w=f(x,y) How do I solve this in Maple, do I maybe need more conditions to solve this? Regard, Michel

Hello dear Maple users! I have the following problem that I am trying to solve with maple. I have a set of data points (i made these up for now, the real set has more points) x:=( 1,2,3,4,5,6,7,8 ) y:=( 1,2,3,4,5,6,7,8 ) z:=( 3,1,3,2,4,7,7,9 ) Now, I know how to surface fit this and get maple to formulate an equation for z=f(x,y) with the following statement: w:=(Statistics:-Fit(a + b*x + c*y + d*x^2 + e*x*y+f*y^2,