Given : $$x+[\frac{1}{(x+7)}]=0$$ -----------(i)
=> $$\frac{x^2+7x+1}{x+7}=0$$
=> $$x^2+7x+1=0$$
=> $$x=\frac{-7\pm\sqrt{49-4}}{2}$$
=> $$x=\frac{3\sqrt{5}-7}{2}$$ -----------(ii)
From equation (i), => $$\frac{1}{(x+7)}=-x$$ ---------------(iii)
To find : $$x-[\frac{1}{(x+7)}]$$
Substituting values from equations (ii) and (iii), we get :
= $$x-(-x)=2x$$
= $$2\times\frac{3\sqrt5-7}{2}$$
= $$3\sqrt5-7$$
=> Ans - (B)
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