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Question
Using identity, find the value of (4.9)2
Solution
(4.9)2 = (5 – 0.1)2
Substituting a = 5 and b = 0.1 in
(a – b)2 = a2 – 2ab + b2, we have
(5 – 0.1)2 = 52 – 2(5)(0.1) + (0.1)2
(4.9)2 = 25 – 1 + 0.01 = 24 + 0.01
(4.9)2 = 24.01
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