9 A curve has equation
$$x ^ { 2 } y ^ { 2 } + x y ^ { 4 } = 12$$
9
- Prove that the curve does not intersect the coordinate axes.
9 - Show that \(\frac { \mathrm { d } y } { \mathrm {~d} x } = - \frac { 2 x y + y ^ { 3 } } { 2 x ^ { 2 } + 4 x y ^ { 2 } }\)
9
- (ii) Prove that the curve has no stationary points.
9 - (iii) In the case when \(x > 0\), find the equation of the tangent to the curve when \(y = 1\)