Let - be a binary operation defined on set of rational numbers- by a - b-a b-10- Find the identity element-

An element e is called an identity element for * if a * e = a ⇒ae/10=a ⇒ e=10 Hence, the identity element is 10. ...

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Standard XII

Mathematics

Binary Operation

Let * be a bi...

Question

Let * be a binary operation defined on set of rational numbers, by a * b = $\frac{a b}{10}$ . Find the identity element.

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Solution

An element e is called an identity element for * if a * e = a

$\Rightarrow \frac{a e}{10} = a \Rightarrow e = 10$

Hence, the identity element is 10.

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Let * be a binary operation defined on set of rational numbers, by a * b =ab10. Find the identity element.

An element e is called an identity element for * if a * e = a ⇒ae10=a ⇒ e=10 Hence, the identity element is 10.

Let * be a binary operation defined on set of rational numbers, by a * b = $\frac{a b}{10}$ . Find the identity element.

An element e is called an identity element for * if a * e = a

$\Rightarrow \frac{a e}{10} = a \Rightarrow e = 10$

Hence, the identity element is 10.