Sagot :
bonjour
I = ( x + 1 ) ( x + 5 )
I = x² + 5 x + x + 5
I = x² + 6 x + 5
J = ( 2 - 3 x ) ( 3 + x )
J = 6 + 2 x - 9 x - 3 x²
J = - 3 x² - 7 x + 6
K = ( x - 3 ) ( 5 - 2 x )
K = 5 x - 2 x² - 15 + 6 x
K = - 2 x² + 11 x - 15
Réponse :
Explications étape par étape :
Bonjour
I = (x + 1)(x + 5)
I =x × x + x × 5 + 1 × x + 1 × 5
I = x² + 5x + x + 5
I = x² + 6x + 5
J = (2 – 3x)(3 + x)
J = 2 × 3 + 2 × x - 3x × 3 - 3x × x
J = 6 + 2x - 9x - 3x²
J = 6 - 7x - 3x²
J = - 3x² - 7x + 6
K = (x - 3)(5 – 2x)
K = x × 5 + x × (-2x) - 3 × 5 - 3 ×(-2x)
K = 5x - 2x² - 15 + 6x
K = - 2x² + 11x - 15