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Using identities, find the value of
(i) 101
2
(ii) 98
2
(iii) (0.98)
2
(iv) 11 × 9
(v) 190 × 190 - 10 × 10
(i) 101
2
= (100 + 1)
2
= 100
2
+ 2 × 100 × 1 + 1
2
= 10000 + 200 + 1 = 10201
(ii) 98
2
= (100 - 2)
2
= 100
2
- 2 × 100 × 2 + 2
2
= 10000 - 400 + 4 = 9604
(iii) 0.98
2
= (1 - 0.02)
2
= 1
2
- 2 × 1 × 0.02 + (0.02)
2
= 1 - 0.04 + 0.0004
= 0.9604
(iv) 11 × 9 = (10+1) (10-1)
= 10
2
- 1
2
= 99
(v) 190 × 190 - 10 × 10 = 190
2
- 10
2
= (190 + 10) (190 - 10)
= 200 × 180
= 36000
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