Problem: If x<0x<0x<0, then β£xβ(xβ1)2β£\mid x-\sqrt{(x-1)^{2}} \midβ£xβ(xβ1)2ββ£ equals
Answer Choices:
A. 111
B. 1β2x1-2 x1β2x
C. β2xβ1-2 x-1β2xβ1
D. 1+2x1+2 x1+2x
E. 2xβ12 x-12xβ1 Solution:
β£xβ(xβ1)2β£=β£xββ£xβ1β£β£=β£xβ(1βx)β£=β£β1+2xβ£=1β2x\left|x-\sqrt{(x-1)^{2}}\right|=|x-|x-1||=|x-(1-x)|=|-1+2 x|=1-2 xβ£β£β£β£βxβ(xβ1)2ββ£β£β£β£β=β£xββ£xβ1β£β£=β£xβ(1βx)β£=β£β1+2xβ£=1β2x.