Răspunsuri

2014-09-02T18:05:49+03:00
[(4x+1)² -(2x+3)²]=  [(4x+1)-(2x+3)][(4x+1)+(2x+3)]=  

=(4x+1-2x-3)(4x+1+2x+3)=

=(6x-2)(6x+4)=

=2(3x-1)(3x+2)