If $$x+\frac{1}{x}=-2$$, then the value of $$x^7+\frac{1}{x^7}$$ is
Expression : $$x+\frac{1}{x}=-2$$
=> $$\frac{x^2+1}{x}=-2$$
=> $$x^2+1+2x=0$$
=> $$(x+1)^2=0$$
=> $$x=-1$$
To find : $$x^7+\frac{1}{x^7}$$
= $$(-1)^7+\frac{1}{(-1)^7}$$
= $$-1-1=-2$$
=> Ans - (D)
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