Réponse :
Explications étape par étape
Bonsoir
Factoriser:
0,2×5+5×3,8= 5(0,2 + 3,8)
15×9+99+9×4= 15 x 9 + 11 x 9 + 9 x 4 = 9(15 + 11 + 4)
0,1×3-0,1×2+0,1×9= 0,1(3 - 2 + 9)
Reduire:
x(1/2x)= 1/2
développer:
x(x+6)-x= x^2 + 6x - x = x^2 + 5x
3x(x+4)-6x²= 3x^2 + 12x - 6x^2 = -3x^2 + 12x
x(y-2)+3xy= xy - 2x + 3xy = 4xy - 2x
5x (x²-6)+2x²= 5x^3 - 30x + 2x^2 = 5x^3 + 2x^2 - 30x
Compléter:
(...+3)=16x²+...+...
(4x + 3)^2 = 16x^2 + 24x + 9
4a²-...=(...+3)×(...-...)
4a^2 - 9 = (2a + 3)(2a - 3)
Factoriser:
(x-3)²-2x(x-3)= (x - 3)(x - 3 - 2x) = (x - 3)(-x - 3)
2x (x-1)-4(1-x)= 2x(x - 1) + 4(x - 1) = (x - 1)(2x + 4) = (x - 1) * 2(x + 2) = 2(x - 1)(x + 2)
25-9²= 5^2 - 9^2 = (5 - 9)(5 + 9)
(x+3)²+x²-9= (x + 3)^2 + (x - 3)(x + 3) = (x + 3)(x + 3 + x - 3) = (x + 3)(2x) = 2x(x + 3)
