Proposition: Multiplying Negative and Positive Real Numbers
The multiplication of negative and positive real numbers follows the following rules:
 A positive real number times a positive real number gives a positive real number, symbolically
\[( + )\cdot ( + )=( + )\]
 A negative real number times a positive real number gives a negative real number.
\[(  )\cdot ( + )=(  )\]
 A negative real number times a negative real number gives a positive real number.
\[(  )\cdot (  )=( + )\]
 Zero times any real number gives zero.
\[( 0 )\cdot ( \pm )=( 0 )\]
Table of Contents
Proofs: 1
Mentioned in:
Parts: 1
Proofs: 2 3 4 5
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References
Bibliography
 Piotrowski, Andreas: Own Research, 2014