Example:Tricky set comprehension membership

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Revision as of 12:12, 24 January 2020 by {{GENDER:Mdg39|[math]'"2}} [/math]'"7
(<math>1) </math>2 | <math>3 (</math>4) | <math>5 (</math>6)

Note that set comprehension notation can sometimes be tricky. Just because [math]x ∈ \href{/cs2800/wiki/index.php/Set_comprehension}{\{x \mid P(x)\}} [/math], doesn't necessarily mean [math]x [/math] satisfies [math]P(x) [/math].

For example, we know that [math]-3 + 4 \href{/cs2800/wiki/index.php/%5Cin}{\in} \{x + y \mid x \gt 0\} [/math], because [math]-3 + 4 = 1 = 4 + -3 [/math], but that doesn't mean that [math]-3 \gt 0 [/math].