|
a)
|
Ecris les produits suivants sous forme de sommes. |
a
.
(b +
c) = |
= a . b + a . c |
| = ab + ac | |
|
|
|
3
. (a +
b) |
= 3 . a + .3 . b |
| = 3a + 3b | |
|
|
|
2a
. (3b +
c) |
= 2a . 3b + 2a . c |
| = 6ab + 2ac | |
|
|
|
a
.
(a +
b) |
= a . a + a . b |
| = a2 + ab | |
|
|
|
3a
. (2a
+ 5b) |
= 3a . 2a + 3a . 5b |
| = 6a2 + 15 ab | |