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प्रश्न
Using suitable identities, evaluate the following.
9.8 × 10.2
उत्तर
We have,
9.8 × 10.2 = (10 – 0.2)(10 + 0.2)
= 102 – (0.2)2 ...[Using the identity, (a + b)(a – b) = a2 – b2]
= 100 – 0.04
= 99.96
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