Sagot :
bonjour
A = (2x+3)(3-x)
= 6x -2x² +9 -3x
= -2x² + 3x + 9
B = 3(x-4) - (2x-4)
= 3x - 12 - 2x + 4
= x - 8
A = (x+1)(2x+1)+(3-2x)(x+1)
= (x+1) ( 2x+1 +3 - 2x )
= ( x+1) ( 4)
= 4 ( x + 1 )
B = x² - 49
= x² - 7²
= (x+7)(x-7)
bonne continuation
Bonjour,
Développer :
[tex]A= (2x+3)(3-x)\\\\<=> 6x-2x^2+9-3x\\\\<=>-2x^2+3x+9[/tex]
[tex]B= 3(x-4)-(2x-4)\\\\<=> 3x - 12 - 2x + 4\\\\<=> x -8[/tex]
Factoriser :
[tex]A= (x +1 ) (2x+1) + (3-2x) (x+1)\\\\<=> (x+1) [(2x+1)+(3-2x)]\\\\<=> (x+1) [2x+1+3-2x]\\\\<=>(x+1) [4]\\\\<=> 4(x+1)\\\\[/tex]
[tex]B= x^2-49\\\\<=> (x-7) (x+7)\\[/tex]
Voilà !