Is $y+1$ substitutable for x in $∃y(x = 2y)$?
My answer would be no because if we substitute $x$ for $y+1$ we'd have $∃y(y+1 = 2y)$ which changes the original meaning, which would be that x is an even number. Is this the correct way to justify it?
2026-04-13 15:41:38.1776094898
Is $y+1$ substitutable for x in the following expression?
33 Views Asked by user105475 https://math.techqa.club/user/user105475/detail AtRelated Questions in FIRST-ORDER-LOGIC
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