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Question
Evaluate following using identities:
(a - 0.1) (a + 0.1)
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Solution
In the given problem, we have to evaluate expressions by using identities.
The given expression is (a + 0.1)(a - 0.1)
We shall use the identity `(x + y)(x - y) = x^2 - y^2`
Here x = a
y = 0.1
By applying identity we get
`(a + 0.1)(a - 0.1) = (a)^2 - (0.1)^2`
`= (a xx a) - (0.1 xx 0.1)`
`= a^2 - 0.01`
Hence the value of (a + 0.1)(a - 0.1) is `a^2 - 0.01`
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