Sagot :
Heyyyyy
Réponse :
A= 2x²+13x+15
B= 36x²-102x+72
Explications étape par étape :
A= ( x + 5 ) ( 2x + 3 )
A= x×2x +x×3 +5×2x+5×3
A= 2x²+3x +10x+15
A= 2x²+13x+15
B= ( 9x - 12 ) ( 4x - 6 )
B= 9x×4x +9x×(-6) -12×4x -12×(-6)
B= 36x²-54x-48x +72
B= 36x²-102x+72
Rappel :
(a+b)(c+d)= a×c+a×d+b×c+b×d= ac+ad+bc+bd
#ApprendsAvecNosDevoirs
#MeryemML♡
Bonsoir,
Double distributivité
A= ( x + 5 ) ( 2x + 3 )
x*2x = 2x²
x* 3 = 3x
5*2x = 10x
5*3 = 15
=> 2x² +3x +10x +15 = 2x² +13x +15
B= ( 9x - 12 ) ( 4x - 6 )
9x * 4x = 36x²
9x* -6 = -54x
-12* 4x = -48x
-12* -6 =72
=> 36x² -54x -48x +72 =36x² -102x +72