Matematyka z kluczem 8. Zeszyt ćwiczeń | Strona 34 | Zadanie 2
Uzupełnij tabelę i dokończ obliczenia.
a)
| x | -1 | |
| 2x | 2x2 | -2x |
| -3 | -3x | 3 |
(2x – 3)(x – 1) =
= 2x2 – 2x – 2x + 3 =
= 2x2 – 5x + 3
b)
| 3a | -4 | |
| a | 3a2 | -4a |
| 5 | 15a | -20 |
(a + 5)(3a – 4) =
= 3a2 – 4a + 15a – 20 =
= 3a2 + 11a – 20
c)
| 5a | -b | |
| a | 5a2 | -ab |
| 2b | 10ab | -2b2 |
(a + 2b)(5a – b) =
= 5a2 – ab + 10ab – 2b2 =
= 5a2 + 9ab – 2b2