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If * is Def D the Identit Ined on the Set R of All R Y Element If Exist in R Wi Eal Number by Th Respect *: to * Solution - Mathematics

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प्रश्न

If * is defined on the set R of all real number by *: a * b = `sqrt(a^2 + b^2)` find the identity element if exist in R with respect to *

योग

उत्तर

As per the question

Let b be the identify element then

a * b = b * a = a

a * b = `sqrt((a)^2 + (b)^2)` = a

⇒ `(a)^2 + (b)^2 = (a)^2`

⇒ b = 0

Similarly,

 b * a = `sqrt((b)^2 + (a)^2)` = a

⇒ `(b)^2 + (a)^2 = (a)^2`

⇒ b = 0

Therefore, 0 is the identity element.

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2018-2019 (March) 65/3/1

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