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Lesson
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Rule

Identity Property of Multiplication

Any number multiplied by is equal to the number itself.
Because of this, the number is called the Multiplicative Identity.

Proof

Informal Justification
Consider a number By the definition of multiplication, multiplied by another number can be written as times the addition of
If the sum has only one term.
Therefore, is equal to Also, by the Commutative Property of Multiplication,
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