How can I solve it?

7. [-/7.69 Points] DETAILS WANEFMAC7 15.2.018. Calculate of of of and of ax ay ax (1, -1)' ay (1, -1) when defined. (If an answer is undefined, enter UNDEFINED.) f ( x, y ) = 4xe9xy of ax of ay of ax (1, -1) of ay (1, -1) 8. [-/7.69 Points] DETAILS Find fxx(x, y), fy(x, y), fxy(x,y), and fyx(x, y). f ( x, y) = 8x2y fxx ( x , y ) = fry ( x, y ) = f xy ( x, y ) = fyx (x, y ) = Evaluate them all at (1, -1) if possible. (If an answer is undefined, enter UNDEFINED.) fxx(1, -1) = fyy (1, - 1) = fxy ( 1, - 1 ) = fyx(1, -1) = 9. [-/7.69 Points] DETAILS WANEFMAC7 15.2.026. Find Of a2f a2f , and of ax2 ay2 axay ayax f ( x, y ) = e2x +y a2f 2x2 a2f ay2 a2f axay a2f ayax Evaluate them all at (1, -1) if possible. (If an answer is undefined, enter UNDEFINED.) (1, -1) = a2f avz (1, -1) = azf (1, -1) = axay asf ( 1, - 1 ) = ayax