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If $$(x-\frac{1}{x})=3$$, then what is the value of $$(x^{3}-\frac{1}{x^{3}})$$ ?
Given : $$(x-\frac{1}{x})=3$$ ----------(i)
Cubing both sides, we get :
=> $$(x-\frac{1}{x})^3=(3)^3$$
=> $$x^3-\frac{1}{x^3}-3(x)(\frac{1}{x})(x-\frac{1}{x})=27$$
=> $$x^3-\frac{1}{x^3}-3(1)(3)=27$$
=> $$(x^{3}-\frac{1}{x^{3}})=27+9=36$$
=> Ans - (A)
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