Question

Salut
Ma poate ajuta cineva cu exercitiul acesta? As avea nevoie de tot exercitiul scris daca se poate. Multumesc mult.

Answer 1

Explicație pas cu pas:

f1=x²-7x+6=0

delta=49-24=25

x`=(7+5)/2=6; x``=(7-5)/2=1.

f2= 3x²-x-4=0

delta=49;x`=(1+7)/6=4/3;x``=(1-7)/6=-1.

x²-25<=0=>x€[-5,5] (1)

x -inf -1 1 4/3 6 +inf

f1 ++++++0-----------0+++++

f2 ------|++++++|---------------

f1/f2 -----|++0----|++++0-------

=>x€(-inf,-1) U (1,4/3) U(6,+inf) (2)

In final x€(1) n (2)=>x€[-5,-1) U (1,4/3).