Expression : $$(a+\frac{1}{a})^2=3$$
=> $$a^2+\frac{1}{a^2}+2(a)(\frac{1}{a})=3$$
=> $$a^2+\frac{1}{a^2}=3-2=1$$
Squaring both sides, we get :
=> $$(a^2+\frac{1}{a^2})^2=(1)^2$$
=> $$a^4+\frac{1}{a^4}+2(a^2)(\frac{1}{a^2})=1$$
=> $$a^4+\frac{1}{a^4}=1-2=-1$$ -----------(i)
$$\therefore$$Â $$a^6-\frac{1}{a^6}=(a^2)^3-(\frac{1}{a^2})^3$$
Using, $$x^3-y^3=(x-y)(x^2+y^2+xy)$$
= $$(a^2-\frac{1}{a^2})\times[a^4+\frac{1}{a^4}+(a^4)(\frac{1}{a^4})]$$
Substituting value from equation (i),
= $$(a^2-\frac{1}{a^2})\times(-1+1)=0$$
=> Ans - (C)
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