Why does the distributive property fail when comparing expressions?

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Stephen Prunty
Stephen Prunty am 18 Apr. 2018
Beantwortet: Star Strider am 18 Apr. 2018
As a simplified example, I'm trying to compare whether two expressions are equal, where they are simply written differently. But
syms a x y;
logical((x+y)*a == x*a + y*a)
returns false, and everything else that assumes distributivity of + and *. Is there some other function that will help me, or some explanation why this happens?
  1 Kommentar
Stephen Prunty
Stephen Prunty am 18 Apr. 2018
Ah, just found out apparently using simplify on both sides of the equals returns true.

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Antworten (1)

Star Strider
Star Strider am 18 Apr. 2018

To get logical results with symbolic expressions, use the isAlways (link) function.

syms a x y;
TF = isAlways((x+y)*a == x*a + y*a)
TF =
    logical
     1

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