id3 := .001;f := (x1,x2) ->((1+id3)*x1+(1-id3)*x2)*exp(-(x1+(1+id3)*x2)) -x1;

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f(x1,x2);

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dfdxA := diff(f(x1,x2),x1);

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dfdxA := (x1,x2) -> (1+id3)*exp(-x1-(1+id3)*x2)-((1+id3)*x1+(1-id3)*x2)*exp(-x1-(1+id3)*x2)-1;

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dfdxB := diff(f(x1,x2),x2);

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dfdxB := (x1,x2) -> (1-id3)*exp(-x1-(1+id3)*x2)-(1+id3)*((1+id3)*x1+(1-id3)*x2)*exp(-x1-(1+id3)*x2);

NiM+SSZkZmR4Qkc2ImYqNiRJI3gxR0YlSSN4MkdGJUYlNiRJKW9wZXJhdG9yR0YlSSZhcnJvd0dGJUYlLCYqJiwmIiIiRjBJJGlkM0dGJSEiIkYwLUkkZXhwRzYkSSpwcm90ZWN0ZWRHRjZJKF9zeXNsaWJHRiU2IywmOSRGMiomLCZGMEYwRjFGMEYwOSVGMEYyRjBGMCooRjxGMCwmKiZGPEYwRjpGMEYwKiZGL0YwRj1GMEYwRjBGM0YwRjJGJUYlRiU=

dfdxB(x1,x2);

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