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Bonjour, je suis en 2nd et j'aurais besoin d'aide pour faire 2 exercices de maths. Ce sont les exercices 101 et 102.

Bonjour Je Suis En 2nd Et Jaurais Besoin Daide Pour Faire 2 Exercices De Maths Ce Sont Les Exercices 101 Et 102 class=

Répondre :

bonjour

a ) ( x - 1 ) ( 2 x + 5 ) +  4 x ² + 20 x + 25

= ( x - 1 ) ( 2 x + 5 ) + ( 2 x +5 )²

= ( 2 x + 5 ) ( x - 1 + 2 x + 5 )

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

b)  9 x² - 81 - 2 x  ( 3 x - 9 )

= ( 3 x  - 9 ) ( 3 x + 9 ) - 2 x ( 3 x - 9 )

= ( 3 x - 9 ) ( 3 x + 9  - 2 x )

= ( 3 x - 9 ) ( x + 9 )

=  3 ( x - 3 ) ( x + 9 )

c ) 5 x - 20 - ( 2 x + 3) ( x - 4 )

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

( x - 4 ) ( 5 - 2 x - 3 )

= ( x - 4 )  *  -2 ( x - 1 )

=  - 2 ( x - 4 ) ( x - 1 )

d ( 2 x + 1 ) - 6 x - 3

= ( 2 x + 1 ) -  3 ( 2 x + 1 )

= ( 2 x + 1 ) ( x - 3 )

a =  ( 2 t - 1 ) ( t - 7 ) - t + 7

= ( 2 t - 1 ) ( t - 7)   -  ( t  - 7 )

= ( t - 7 ) ( 2 t - 1 - 1 )

=  ( t - 7 ) ( 2 t - 2 )

=   2 ( t - 7 ) ( t - 1 )

b =  (6 x - 5 )² + 12 x - 10

= ( 6 x - 5 )²  + 2  ( 6 x - 5 )

= ( 6 x - 5 ) ( 6 x  - 5 + 2 )

= ( 6 x - 5 ) ( 6 x - 3 )

=  3 ( 6 x - 5 ) ( 2 x - 1 )

c) ( 3 z - 5 )³ - 2 z ( 3 z - 5 )²

= ( 3 z - 5 )² ( 3 z - 5 - 2 z)

= ( 3 z - 5 )² ( z - 5 )

( 4 x + 3 ) ( x - 1 ) + 2 x² - 2

= ( 4 x + 3 ) ( x - 1 ) + 2 ( x² -  1  )

= ( 4 x + 3 ) ( x - 1 ) + 2 ( x - 1 ) ( x + 1 )

= ( x  - 1 ) ( 4 x + 3  + 2 x + 2 )

= ( x - 1 ) ( 6 x + 5 )

Réponse :

Explications étape par étape

Bonjour

(x - 1)(2x + 5) + 4x^2 + 20x + 25

= (x - 1)(2x + 5) + (2x)^2 + 2 * 2x * 5 + 5^2

= (x - 1)(2x + 5) + (2x + 5)^2

= (2x + 5)(x - 1 + 2x + 5)

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

9x^2 - 81 - 2x(3x - 9)

= (3x)^2 - 9^2 - 2x(3x - 9)

= (3x - 9)(3x + 9) - 2x(3x - 9)

= (3x - 9)(3x + 9 - 2x)

= 3(x - 3)(x + 9)

5x - 20 - (2x + 3)(x - 4)

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

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

= (x - 4)(-2x + 2)

= (x - 4) * -2(x - 1)

= -2(x - 4)(x - 1)

x(2x + 1) - 6x - 3

= x(2x + 1) - 3(2x + 1)

= (2x + 1)(x - 3)

Exercice 102 :

(2t - 1)(t - 7) - t + 7

= (2t - 1)(t - 7) - (t - 7)

= (t - 7)(2t - 1 - 1)

= (t - 7)(2t - 2)

= (t - 7) * 2(t - 1)

= 2(t - 7)(t - 1)

(6x - 5)^2 + 12x - 10

= (6x - 5)^2 + 2(6x - 5)

= (6x - 5)(6x - 5 + 2)

= (6x - 5)(6x - 3)

= (6x - 5) * 3(2x - 1)

= 3(6x - 5)(2x - 1)

(3z - 5)^3 - 2z(3z - 5)^2

= (3z - 5)^2(3z - 5 - 2z)

= (3z - 5)^2(z - 5)

(4x + 3)(x - 1) + 2x^2 - 2

= (4x + 3)(x - 1) + 2(x^2 - 1)

= (4x + 3)(x - 1) + 2(x - 1)(x + 1)

= (x - 1)[4x + 3 + 2(x + 1)]

= (x - 1)(4x + 3 + 2x + 2)

= (x - 1)(6x + 5)