English: See this is because f has real coefficients, see f is let us say a n x n plus a 1 x plus a 0 where, a i’s are in R. f of i is a n i power n dot dot dot a 1 i plus a 0 this is 0, but now take complex conjugation which is what bar is right, take that.
Telugu: ఇది చూడండి ఎందుకంటే f కి రియల్ కోయెఫిషియంట్స్ ఉన్నాయి, f(x ) =  a _(n )x ^(n )+. . . . . . . . + a ₁x  + a ₀ ,ఇక్కడ a _(i)లు R లో ఉన్నాయి.