Surjakciōni

Surjakciōni ("nō" funkciōni) iz tūliskwan X en tūliskwan Y ast funkciōni, kawīdses pawīda ast pastippa tūlisku Y: $\operatorname {Im} f=Y$

anga liguwīdai: $\forall {y\in Y}\;\exists {x\in X}\;f(x)=y.$

Erainā funkciōni mazzi wīrstwei surjakciōni, panzdau kitawīdinsnas tenesse prikidōmenin na tenesse pawīdan. Īmtun mūisesan dōmenin pernaikinna surjāktibin. Perwaidīnsnai, ik $Y=\mathbb {R} _{+}\cup \{0\}$, staddan funkciōni dātan pra f(x) = x^2 ast surjakciōni. Adder kaddan īmtun $Y=\mathbb {R}$ šī funkciōni ni ast jāu "nō".

Perwaidīnsnas

• $f:x\mapsto {1 \over x}$ pēr $x\in \mathbb {R} \setminus \{0\}$ nō stan subban tūliskwan.
• $f:x\mapsto x^{a}$ pēr $x\in \mathbb {R} ,a\in \{2n+1:n\in \mathbb {N} \}$ nō $\mathbb {R}$
• $f:x\mapsto \ln {x}$ pēr Parsers ni mazēi skaitātun (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle x\in \{r\in \mathbb {R} :r>0\}} nō $\mathbb {R}$
• Parsers ni mazēi skaitātun (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle f:x\mapsto \operatorname {tg} {x}} pēr $x\in \{r\in \mathbb {R} :\pi >2r>-\pi \lor 3\pi >2r>\pi \}$ nō $\mathbb {R}$
• Parsers ni mazēi skaitātun (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle f:\mathbb {R} \to \mathbb {Z} } dātan pra: Parsers ni mazēi skaitātun (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle f(x)=\lceil x\rceil }
• Parsers ni mazēi skaitātun (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle f:2^{2^{\mathbb {R} }}\to \{1\}} dātan pra: $f(x)=1$