Bonjour,
A = 8a + (2a – 2) (3a + 1)=
8a +6a² +2a -6a -2=
6a² +4a -2
B = 17 – (3 – b) (4b – 2)=
17 -(12b -6 -4b² +2b)=
17 -12b +6 +4b² -2b=
4b² -14b +23
C = (3y + 4) (3y – 4)=
9y² -12y +12y -16 =
9y² -16
2) Démontrer que :
A = 8a + (2a – 2) (3a + 1)
B = 17 – (3 – b) (4b – 2)
C = (3y + 4) (3y – 4)
2) Démontrer que : (6n + 4) (4n + 2) = (8n + 4) ( 3n + 2)
(6n + 4) (4n + 2) =
24n² +12n +16n +8 =
24n² +28n +8
(8n + 4) ( 3n + 2)=
24n² +16n +12n +8=
24n² +28n +8
24n² +28n +8 =24n² +28n +8
