Expression : $$(x+\frac{1}{x})^2=3$$
=> $$(x+\frac{1}{x})=\sqrt3$$ ------------(i)
Cubing both sides, we get :
=> $$(x+\frac{1}{x})^3=(\sqrt3)^3$$
=> $$x^3+\frac{1}{x^3}+3(x)(\frac{1}{x})(x+\frac{1}{x})=3\sqrt3$$
Substituting value of $$(x+\frac{1}{x})$$ from equation (i)
=> $$x^3+\frac{1}{x^3}+3\sqrt3=3\sqrt3$$
=> $$x^3+\frac{1}{x^3}=0$$
=> Ans - (A)
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