Sagot :
Réponse :
Bonjour
1) (5x + 3)(2x + 6) = 10x² + 30x + 6x + 18 = 10x² + 36x + 18
2) (4x + 8)(3x + 5) = 12x² + 20x + 24x + 40 = 12x² + 44x + 40
3) (6x - 4)(3x + 5) = 18x² + 30x - 12x - 20 = 18x² + 18x - 20
4) (-3 + 4x)(-2x - 4) = 6x + 12 - 8x² - 16x = -8x² - 10x + 12
bonjour,
1. (5x+3)(2x+6)= 5x*2x+5x*6+3*2x+3*6
= 10x^2+30x+6x+18
= 10x^2+36x+18
2. (4x+8)(3x+5)= 4x*3x+4x*5+8*3x+8*5
=12x^2+20x+24x+40
=12x^2+44x+40
3. (6x-4)(3x+5)= 6x*3x+6x*5-4*3x-4*5
=18x^2+30x-12x-20
=18x^2+18x-20
4. (-3+4x)(-2x-4)= -3*(-2x)-3*(-4)+4x*(-2x)+4x*(-4)
=6x+12-8x^2-16x
=-8x^2-10x+12
1. (5x+3)(2x+6)= 5x*2x+5x*6+3*2x+3*6
= 10x^2+30x+6x+18
= 10x^2+36x+18
2. (4x+8)(3x+5)= 4x*3x+4x*5+8*3x+8*5
=12x^2+20x+24x+40
=12x^2+44x+40
3. (6x-4)(3x+5)= 6x*3x+6x*5-4*3x-4*5
=18x^2+30x-12x-20
=18x^2+18x-20
4. (-3+4x)(-2x-4)= -3*(-2x)-3*(-4)+4x*(-2x)+4x*(-4)
=6x+12-8x^2-16x
=-8x^2-10x+12