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प्रश्न
Evaluate the following using identities:
(2x + y) (2x − y)
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उत्तर
In the given problem, we have to evaluate expressions by using identities.
We have been given (2x + y) (2x − y)
We shall use the identity `(a + b)(a - b)= a^2 -b^2`
Here a = 2x, b = y
By applying identity we get
`(2x + y)(2x - y) = (2x)^2 - (y)^2`
`= (2x xx 2x) - (y xx y)`
`= 4x^2 - y^2`
Hence the value of (2x + y)(2x - y) is `4x^2 - y^2`
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