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प्रश्न
Using suitable identities, evaluate the following.
105 × 95
मूल्यांकन
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उत्तर
We have,
105 × 95 = (100 + 5)(100 – 5)
= (100)2 – (5)2 ...[Using the identity, (a + b)(a – b) = a2 – b2]
= 10000 – 25
= 9975
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अध्याय 7: Algebraic Expression, Identities and Factorisation - Exercise [पृष्ठ २३३]
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