Sagot :
Bonjour,
Compléter:
(a + 5)(a + 7)= a² + 7a + 5a + 35 = a²+12a +35 ***7a+5a= 12
(a - 5)(a + 7)= a²+ 7a - 5a - 35 =a²+2a-35 ***-5fois+7= - 35
(a + 5)(a - 7)=a²+5a-7a-35= a²-2a-35
(a - 5)(a - 7)=a²-5a-7a+35= a²-12a+35
bonjour
[tex]( a + 5 ) ( a + 7 ) = a^{2} + 7 a + 5 a + 35 = a^{2} + 12 a + 35\\\\( a - 5 ) ( a + 7 ) = a^{2} + 7 a - 5 a - 35 = a^{2} + 2 a - 35\\\\( a + 5 ) ( a - 7 ) = a^{2} - 7 a + 5 a - 35 = a^{2} - 2 a - 35 \\\\( a - 5 ) ( a - 7 ) = a^{2} - 7 a - 5 a + 35 = a^{2} - 12 a + 35 \\\\[/tex]