elsal
Answered

bonjour j’ai besoin d’aide pour cet exo
1. Développer et réduire les expressions
suivantes
A = x(x + 2) i
5x(x + 3)
C = 2x(3x - 5)
D = -3x(1 - 4x)
E = (x + 3) + (4x - 5)
F = 6 - 2t - (4t-8)
G = -(8a + 3) - 4a
H = (2y + 7) + (-5y + 3)
I = 5x - 6-(7 - 2x) + 3x
J = (3 - 4x) - (-2x + 8)
2. Réduire chacune des expressions suivantes :
K = x - 6 - 5x2 - 30 - x
= 12x - x? - 10 + x - 3-8x2 + 1 - 2x
M= -3- a + b + 5a - 9+(-3a - 5b)
N = r? - (3x2 - 15 + 4) + (15x2 - 12x - 3)
3. Factoriser les expressions suivantes
P = 49a2 - 28a+b + 4a3b2
Q = 162x3 - 2x
R = 9a +36a2 - 36
S = 2x3 - 12x2 - 54x

Sagot :

reginegalmar

Réponse :

1.

A = x(x + 2) = x² + 2x

B = 5x(x + 3) = 5x² + 15x

C = 2x(3x - 5) = 6x² - 10x

D = -3x(1 - 4x) = - 3X + 12x² = 12x² - 3x

E = (x + 3) + (4x - 5) = x + 3 + 4x - 5 = 5x - 2

F = 6 - 2t - (4t - 8) = 6 - 2t - 4t + 8 = - 6t + 14

G = -(8a + 3) - 4a = - 8a - 3 - 4a = - 12a - 3

H = (2y + 7) + (-5y + 3) = 2y + 7 - 5y + 3 = - 3y + 10

I = 5x - 6 -(7 - 2x) + 3x = 5x - 6 - 7 + 2x + 3x = 10x - 13

J = (3 - 4x) - (-2x + 8) = 3 - 4x + 2x - 8 = - 2x - 5

2.

K = x - 6 - 5x² - 30 - x = -5x² - 36

L = 12x - x - 10 + x - 3 - 8x² + 1 - 2x = -8x² + 10x - 12

M = -3 - a + b + 5a - 9 + (-3a - 5b) = -3 - a + b + 5a - 9 - 3a - 5b = a - 4b - 12

3.

Q = 162x^3 - 2x = 2x(81x² - 1)

S = 2x^3 - 12x² - 54x = 2x(x² - 6x - 27)

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