Sagot :
bjr
vous savez que k (a + b) = k * a + k * b
donc
1) 4 (y + 6 ) = 4 * y + 4 * 6 = 4y + 24
2) -5( 6 - 2b) = -5 * 6 - 5 * (-2b) = -30 + 10b
3) (10y + 4) x 7 = 7 * 10y + 7 * 4 = .... + ....
4) (9b - 3)2b = 2b * 9b + 2b * (-3) = ... - ....
Factoriser les expressions suivante :
1) 9y - 9b = 9 * y - 9 * b = 9 ( y - b)
2) t² + 4t = t * t + t * 4 = t (t+4)
3) 10n - 22n = -12n (simple calcul)
4) 6b² + 36b = 6b * b + 6b * 6 = 6b (.. + ...)
Réponse :
1* 4(y+6) = 4 x y + 4 x 6= 4y + 24
2* -5(6-2b) = -5 x 6 - (-5) x (-2b)= -30 + 10b
3* (10y + 4) x 7 = 7 x 10y + 7 x 4 = 70y + 28
4* (9b - 3)2b = 9b x 2b - 3 x 2b = 18[tex]b^{2}[/tex] - 6b
1* 9y-9b = 9 x y - 9 x b = 9 (y-b)
2* t² + 4t = t x t + 4 x t = t (4 x t)
3* 10n - 22n = 10 x n - 22 x n = n (10 - 22) = n(-12)
4* 6b² + 36b = b x 6b + 6 x 6b = 6b(b x 6)