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The product of all the rational roots of the equation $$(x^2 - 9x + 11)^2 - (x - 4)(x - 5) = 3$$ is equal to:
$$(x^2 - 9x + 11)^2 - (x - 4)(x - 5) = 3$$
$$(x-4)(x-5)=x^2-9x+20$$
Let $$x^2-9x+20=t$$
$$\left(t-9\right)^2-t=3$$
$$t^2-19t+78=0$$
$$\left(t-13\right)\left(t-6\right)=0$$
So, $$t=13\ ,\ 6$$
Now, two cases will be formed:Â
Case 1: $$t=13$$
$$x^2-9x+20=13$$
$$x^2-9x+7=0$$
The discriminant is $$\sqrt{53}$$. So, all the roots will be irrational.Â
Case 2:Â $$t=6$$
$$x^2-9x+20=6$$
$$x^2-9x+14=0$$
$$\left(x-7\right)\left(x-2\right)=0$$
$$x=2\ ,\ 7$$
These roots are rational.Â
We have to find the product of rational roots.Â
Product =Â $$\left(2\times7\right)=14$$
$$\therefore\ $$ The required answer is A.
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