Talk:Test function

Typographical and Grammatical Fixes

To the best of my knowledge:

• Missing Word: In the "Use in weak formulations" section, there is a missing word in the final paragraph:

"In this formulation, the test functions need not themselves be smooth: they can [belong] to the Sobolev space obtained as a completion..."

One needs to insert the word "belong" (or "be in") to make the sentence grammatically correct.

• Equation Formatting Consistency: In the Schwartz space section, the norm definition uses a non-breaking space and slightly different spacing:

$\|\varphi \|_{k}=\max _{|\alpha |+|\beta |\leq k}\sup _{x\in \mathbf {R} ^{n}}\left|x^{\alpha }D^{\beta }\varphi (x)\right|$ for k ≥ 1. For consistency with Wikipedia's manual of style regarding LaTeX blocks, one should move the condition inside the $tags,likethis:<math>\|\varphi \|_{k}=\max _{|\alpha |+|\beta |\leq k}\sup _{x\in \mathbf {R} ^{n}}\left|x^{\alpha }D^{\beta }\varphi (x)\right|\quad {\text{for }}k\geq 1.$ Викидим (talk) 13:32, 24 May 2026 (UTC)