rezolvi ecuatia x²-5x+6=0 x1=2 x2=3 intre radacini este negativa, in afara radacinii pozitiva
x-1 >0 pt x>1 si X-1<0 py x<1
facitabelul
x l-∞___________0 _____1_____2_____3_________________+∞
(x²-5x+6)l++++++++++++++++++0-- - - -0+ + +++++++++++++
_________________________________________________________
x-1 l- - - - - - - - - - - - - - - - 0++++++++++++++++++++++++++++
________________________________________________________
(x-1)*(x²-5x+6)- - -_ - - - - - 0+++0- - - - - 0 +++++++++++++++=
Retii acele intervale unde pe ultimul rand apare (-) adica (-∞ 1]U[2 3]