103 × 107
103 × 107 = (100 + 3) × (100 + 7)
= (100)2 + (3 + 7) (100 + (3)(7))
| Using Identity IV
= 10000 + 1000 + 21 = 11021.
Aliter
103 × 107 = (105 - 2) × (105 + 2)
= (105)2 - (2)2
| Using Identity III
= (100 + 5)2 - 4
= (100)2 + 2(100)(5) + (5)2 - 4
| Using Identity I
= 10000 + 1000 + 25 - 4 = 11021.