Otvoreni interval ( ne sadrži svoje granice)

\[\left\langle a,b\right\rangle =\left\lbrace x\in R:a<x<b\right\rbrace \]

Zatvoreni interval - segment ( sadrži svioje granice)

 \[  \left[ a,b\right] =\left\lbrace x\in R:a\leq x\leq b\right\rbrace  \]

Poluotvoreni ( poluzatvoreni ) inerval ( otvoren s lijeva, zatvoren s desna)

\[ \left\langle a,b\right] =\left\lbrace x\in R:a < x\leq b\right\rbrace \]

Poluotvoreni ( poluzatvoreni ) inerval ( zatvoren s lijeva, otvoren s desna )

\[ \left[ a,b\right\rangle =\left\lbrace x\in R:a\leq x < b\right\rbrace \]

Za  \( a\in R \) definiramo intervale

\[ \left\langle -\infty, a \right\rangle = \left\lbrace x\in R | x<a \right\rbrace \]

\[ \left\langle -\infty, a \right] = \left\lbrace x\in R | x\leq a \right\rbrace \]

\[ \left\langle a,\infty \right\rangle = \left\lbrace x\in R | x>a \right\rbrace \]

\[ \left[ a,\infty \right\rangle = \left\lbrace x\in R | x\geq a \right\rbrace \]

i posebno za \( a=0 \)

\[ \left\langle -\infty, 0 \right\rangle = \left\lbrace x\in R | x<0 \right\rbrace \]

\[ \left\langle -\infty, 0 \right] = \left\lbrace x\in R | x\leq 0 \right\rbrace \]

\[ \left\langle 0,\infty \right\rangle = \left\lbrace x\in R | x>0 \right\rbrace \]

\[ \left[ 0,\infty \right\rangle = \left\lbrace x\in R | x\geq 0 \right\rbrace \]