SOLUTION: Find the value of {{{(dy)/(dx)}}} when x= -1 and y= 1, given that {{{3x^2+4xy-xy^3 = 0}}}

1)  Differentiate implicitly

        6x*(dx) + 4*(dx)*y + 4x*(dy) - (dx)y^3 - x*3y^2*(dy) = 0.



2)  Substitute here x= -1, y= 1

        -6*(dx) + 4*(dx)*1 + 4*(-1)*(dy) - (dx)*1^3 - (-1)*3*1^2*(dy) = 0.



3)  Collect like terms


        -6*(dx) + 4*(dx) - (dx) = 4*(dy) - 3*(dy)

        -3*(dx)                 = (dy)



4)    = -3.             ANWER