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प्रश्न
Determine whether * is a binary operation on the sets-given below.
a * b – a.|b| on R
उत्तर
Yes.
Reason: a, b ∈ R.
So, |b| ∈ R
When b ∈ R
Now multiplication is binary on R
So a|b| ∈ R when a, b ∈ R.
(Le.) a * b ∈ R.
* is a binary operation on R
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