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Prealgebra 2e

Key Terms

Prealgebra 2eKey Terms

Key Terms

Additive Identity
The additive identity is 0. When zero is added to any number, it does not change the value.
Additive Inverse
The opposite of a number is its additive inverse. The additive inverse of a is −a−a.
Irrational number
An irrational number is a number that cannot be written as the ratio of two integers. Its decimal form does not stop and does not repeat.
Multiplicative Identity
The multiplicative identity is 1. When one multiplies any number, it does not change the value.
Multiplicative Inverse
The reciprocal of a number is its multiplicative inverse. The multiplicative inverse of a is 1a1a.
Rational number
A rational number is a number that can be written in the form pqpq, where p and q are integers and q≠0q≠0. Its decimal form stops or repeats.
Real number
a real number is a number that is either rational or irrational.
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