Question

Find the gradient of xy^2 + x^2y=4xy at the point (1,3)?

Answer 1

If you mean dy/dx, then

D( xy^2 + x^2y)=D(4xy)
y^2+2yy'+2xy+x^2 y'=4y+4xy'
y'(2y+x^2-4x)=4y+y^2+2xy
so at point 1,3
y'(6+1-4)=12+9+6
y'=37/3
check that.

Answer 2

Find the gradient of the tangent line of x^2y+xy^2=xy at (-1;2)