Sagot :
Bonjour,
Réduire:
A = (x – 3)(x + 2) + 4 + 2(x + 2)
A= x²-3x+2x-6+4+2x+4
A= x²+x+2
B = (x + 1)(3 – x) – 2(x – x²)
B= 3x+3-x²-x-2x+2x²= x²+3
C = 3(2x + 4) – (15 + x) + (2 – x)(3 – x)
C= 6x+12-15-x+6-3x-2x+x²
C= x²+3
Réponse :
Bonjour,
Explications étape par étape
A = (x – 3)(x + 2) + 4 + 2(x + 2)
A= x×x+x×2-3×x-3×2 +4 +2×x+2×2
A=x²+2x-3x-6 +4 +2x+4
A= x²+2x-3x+2x-6+4+4
A= x²+x+2
B = (x + 1)(3 – x) – 2(x – x²)
B= x×3+x×x+1×3+1×(-x) -2×x-2×(-x²)
B= 3x-x²+3-x -2x+2x²
B= -x²+2x²+3x-x-2x+3
B= x²+0x+3
B=x²+3
C = 3(2x + 4) – (15 + x) + (2 – x)(3 – x)
C= 3×2x+3×4 -15-x +2×3+2×(-x)-x×3 -x ×(-x)
C= 6x+12-15-x+6-2x-3x+x²
C=x²+6x-x-2x-3x+12-15+6
C= x²+0x+3
C=x²+3