| f) | Complète les égalités suivantes. |
Exercice n°1
| (5 x – 3) . (5 x + 3) = 25 x2 – 9 | (4 – 5 a) . (4 + 5 a) = 16 – 25 a2 |
| (4 x – 5 y) . (4 x + 5 y) = 16 x2 – 25 y2 | (1 + xy) . (1 – xy) = 1 – x2y2 |
| (a + 7) . (a – 7) = a2 – 49 | (5 + a) . (5 – a) = 25 – a2 |
| (x + 1) . (x – 1) = x2 – 1 | (a – 7 b) . (a + 7 b) = a2 – 49 b2 |
(3 a + 2 b) . (3 a – 2 b) = 9 a2 – 4 b2 |
(x
+ .........) . (1 – .......)
= ....... – ....... (......... + x) . (1 – .......) = ....... – ....... (1 + x) . (1 – x) = 1 – x2 |