30 11 Множення многочленів

( х+ у ) ( a + b) = ax + by

( х+ у ) ( a + b) = ax + bx

( х+ у ) ( a + b) = ax + bx + ay+ by

= a² + 3a + 5a + 3

= 2a + 3a + 5a + 15

= a² + 3a + 5a + 15

( х- у ) ( a + b) = ax - by

( х- у ) ( a + b) = ax + bx

( х- у ) ( a + b) = ax + bx - ay- by

= a² -2а + 3a + 3

= 2a + 3a + -6

= a² - 2a + 3a + 15