(i) 2a3 (3a + 5b)
= 2a3 (3a + 5b)
= (2a3 × 3a) + (2a3 × 5b)
= 6a4 + 10a3b
(ii) -11a (3a + 2b)
= -11a (3a + 2b)
= (-11a × 3a) + (-11a × 2b)
= -33a2 – 22ab
(iii) -5a (7a – 2b)
= -5a (7a – 2b)
= (-5a × 7a) – (-5a × 2b)
= -35a2 + 10ab
(iv) -11y2 (3y + 7)
= -11y2 (3y + 7)
= (-11y2 × 3y) + (-11y2 × 7)
= -33y3 – 77y2
