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The locus of the foot of perpendicular drawn from the centre of the ellipse $$x^2 + 3y^2 = 6$$ on any tangent to it is:
We start with the given ellipse
$$x^{2}+3y^{2}=6.$$
It is convenient to write it in the standard form
$$\frac{x^{2}}{6}+\frac{y^{2}}{2}=1,$$
so that we can recognise the semi-axes $$a^{2}=6$$ and $$b^{2}=2.$$
For any point $$\,(x_{1},y_{1})$$ lying on the ellipse, i.e.
$$x_{1}^{2}+3y_{1}^{2}=6,$$
the equation of the tangent at that point is obtained by the tangent in the form $$T=0$$ formula:
$$xx_{1}+3yy_{1}=6.$$
The centre of the ellipse is the origin $$O(0,0).$$ We are required to find the locus of the foot of the perpendicular drawn from this origin to an arbitrary tangent. Let the foot of that perpendicular be $$P(h,k).$$
Because $$OP$$ is perpendicular to the tangent, the vector $$\overrightarrow{OP}=(h,k)$$ must be parallel to the normal vector of the tangent. For the line
$$xx_{1}+3yy_{1}=6,$$
the normal vector is clearly $$\bigl(x_{1},\,3y_{1}\bigr).$$ Hence there is some scalar $$t$$ such that
$$h=t\,x_{1},\qquad k=t\,(3y_{1}).$$
Point $$P(h,k)$$ itself lies on the tangent, so we substitute $$x=h,\;y=k$$ into the tangent’s equation:
$$x_{1}h+3y_{1}k=6.$$ Substituting $$h=t\,x_{1}$$ and $$k=t\,3y_{1}$$ gives
$$x_{1}(t\,x_{1})+3y_{1}(t\,3y_{1})=t\bigl(x_{1}^{2}+9y_{1}^{2}\bigr)=6.$$
Therefore
$$t=\frac{6}{x_{1}^{2}+9y_{1}^{2}}.$$
Using this value of $$t$$ we can express $$h$$ and $$k$$ completely in terms of $$x_{1},y_{1}:$$
$$h=\frac{6x_{1}}{x_{1}^{2}+9y_{1}^{2}},\qquad k=\frac{18y_{1}}{x_{1}^{2}+9y_{1}^{2}}.$$
Our goal is to eliminate $$x_{1},y_{1}$$ to obtain a relation between $$h$$ and $$k$$ only. To that end we let
$$D=x_{1}^{2}+9y_{1}^{2},$$
so that the above formulae become
$$h=\frac{6x_{1}}{D},\qquad k=\frac{18y_{1}}{D}.$$
From these we solve for $$x_{1}$$ and $$y_{1}$$:
$$x_{1}=\frac{hD}{6},\qquad y_{1}=\frac{kD}{18}.$$
Since $$\,(x_{1},y_{1})$$ lies on the ellipse, it satisfies
$$x_{1}^{2}+3y_{1}^{2}=6.$$
Substituting the expressions for $$x_{1}$$ and $$y_{1}$$ gives
$$\left(\frac{hD}{6}\right)^{2}+3\left(\frac{kD}{18}\right)^{2}=6.$$
Expanding, we obtain
$$\frac{h^{2}D^{2}}{36}+\frac{k^{2}D^{2}}{108}=6.$$
Factorising $$\dfrac{1}{108}$$ out of the brackets,
$$\frac{D^{2}}{108}\bigl(3h^{2}+k^{2}\bigr)=6,$$ so
$$D^{2}=\frac{648}{3h^{2}+k^{2}}.$$
On the other hand, by definition
$$D=x_{1}^{2}+9y_{1}^{2}=\frac{h^{2}D^{2}}{36}+\frac{k^{2}D^{2}}{36} = \frac{D^{2}(h^{2}+k^{2})}{36}.$$
Dividing both sides by $$D\ (\neq 0)$$ gives
$$1=\frac{D(h^{2}+k^{2})}{36},\qquad\text{so}\qquad D=\frac{36}{h^{2}+k^{2}}.$$
Squaring this last relation,
$$D^{2}=\frac{1296}{(h^{2}+k^{2})^{2}}.$$
We now have two separate expressions for $$D^{2}$$, so we equate them:
$$\frac{1296}{(h^{2}+k^{2})^{2}}=\frac{648}{3h^{2}+k^{2}}.$$
Cross-multiplying yields
$$1296\bigl(3h^{2}+k^{2}\bigr)=648\,(h^{2}+k^{2})^{2}.$$
Dividing by $$648$$ simplifies the equation to
$$2\bigl(3h^{2}+k^{2}\bigr)=(h^{2}+k^{2})^{2}.$$
That is,
$$(h^{2}+k^{2})^{2}=6h^{2}+2k^{2}.$$
Replacing $$h$$ by $$x$$ and $$k$$ by $$y$$ (for the locus in the usual $$xy$$-plane) we finally obtain
$$(x^{2}+y^{2})^{2}=6x^{2}+2y^{2}.$$
This exactly matches the equation given in Option A.
Hence, the correct answer is Option A.
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