Réponses

2013-11-03T10:45:02+01:00
(2x-3)²+(x+4)²
=4x²-12x+9+x²+8x+16
=5x²-4x+25

(3x+2)(4x-1)-x(x-1)
=12x²-3x+8x-2-x²+x
=11x²+6x-2

(1-2x)(1+2x)
=1-4x² produit remarquable (a-b)(a+b)=a²-b²
2013-11-03T10:49:35+01:00
(2x-3)²+(x+4)²
4x²-12x+9+x²+8x+16
5x²-4x+25

(3x+2)(4x-1)-x(x-5)
12x²-3x+8x-2-x²+5x
11x²+10x-2

(1-2x)(1+2x)
1+2x-2x-4x²
-4x²+1