(%i5) diff(-log(5*(x-1)^2+5*y^2+1)-log(5*(x+1)^2+5*y^2+1), x); 10 (x + 1) 10 (x - 1) (%o5) - --------------------- - --------------------- 2 2 2 2 5 y + 5 (x + 1) + 1 5 y + 5 (x - 1) + 1 (%i6) diff(-log(5*(x-1)^2+5*y^2+1)-log(5*(x+1)^2+5*y^2+1), y); 10 y 10 y (%o6) - --------------------- - --------------------- 2 2 2 2 5 y + 5 (x + 1) + 1 5 y + 5 (x - 1) + 1
(%i7) solve([diff(-log(5*(x-1)^2+5*y^2+1)-log(5*(x+1)^2+5*y^2+1), x)=0, diff(-log(5*(x-1)^2+5*y^2+1)-log(5*(x+1)^2+5*y^2+1), y)=0]); 2 2 (%o7) [[y = 0, x = 0], [y = 0, x = - -------], [y = 0, x = -------], sqrt(5) sqrt(5) sqrt(6) %i sqrt(6) %i [y = - ----------, x = 0], [y = ----------, x = 0]] sqrt(5) sqrt(5)