Evaluate:
(i) 88 × 92 (ii) 78 × 82.
(i) We have
88 × 92 = (90 – 2) × (90 + 2)
= (902 – 22)
= 8100 – 4
= 8096
(ii) We have
78 × 82 = (80 – 2) × (80 + 2)
= (802 – 22)
= 6400 – 4
= 6396