👤

descompuneti in factori trinomul:
a) 3X la puterea a 2 -2X-1
b) -2X la puterea a 2+5X+3
c) 16X la puterea a 2+8X+1


Răspuns :

a.   3x²  -2x -1 = 2x² +x² -2x -1 = ( x-1 ) ( x+1)  +2x( x-1) = (x-1) ( x+1+ 2x)=
= ( x-1) ( 3x +1 )
b. - 2x² +5x +3=  - 2x² -x +6x +3 = -  x ( 2x +1) + 3 ( 2x +1 ) = ( -x+3) ( 2x+1)
c. 16x² +8x +1= ( 4x +1)²