Which of the following statements is incorrect?

|x|= {−x; x<00; x=0x; x>0  and  sgn(x) ={−1; x<00; x=01; x>0 ∴  (A) xsgnx={−x, if x<00, if x=0x, if x>0⇒ xsgnx=|x| (B) |x|sgnx=(−x)(−1)=x,       if                        x<0                    (0)(0)=0,                       if                        x=0                    (x)(1)=x,                        if                        x>0 ⇒|x|sgnx=x (C) x(sgnx)(sgnx)=x (D) |x|(sgnx)3=(−x)(−1)3=x   if   x<0                      (0)(0)3=0,                       if                        x=0                      (x)(1)3=x,                        if                        x>0 ∴ |x|(sgnx)3=x  not  |x| .