Răspunsuri

2014-07-23T16:26:35+03:00
4-2*2*x+x²+4x-4-x²=4-4x+4x-4+4x=4-4+4x-4x=0
3 4 3
2014-07-23T16:27:28+03:00
(2-x)² + 4(x-1) - x²=
aplicam formula de calcul prescurtat (a-b)
² =a²-2ab+b²
=4-4x+x²+4x-4-x²=0
-x² si x² se reduc 
 4 si -4 se reduc
 -4x si 4x se reduc 
4 4 4