Во проширеното множество реални броеви
(R∪{−∞,+∞}),(R∪{−∞,+∞}), size 12{ \( R union lbrace - infinity ,`+ infinity rbrace \) ,} {}∀a∈R∀a∈R size 12{ forall a in R} {} важи:
a+(+∞)=+∞a+(+∞)=+∞ size 12{a+ \( + infinity \) "=+" infinity } {}, a+(−∞)=−∞a+(−∞)=−∞ size 12{a+ \( - infinity \) = - infinity } {}
a⋅(+∞)=+∞a⋅(+∞)=+∞ size 12{a cdot \( + infinity \) "=+" infinity } {}, a⋅(−∞)=−∞a⋅(−∞)=−∞ size 12{a cdot \( - infinity \) = - infinity } {}, за (a>0)(a>0) size 12{ \( a>0 \) } {}
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size 12{a cdot 0=0} {}
a+∞=a−∞=0a+∞=a−∞=0 size 12{ { {a} over {+ infinity } } = { {a} over { - infinity } } =0} {}, за (a≠0)(a≠0) size 12{ \( a <> 0 \) } {}
0a=00a=0 size 12{ { {0} over {a} } =0} {}, за (a≠0)(a≠0) size 12{ \( a <> 0 \) } {}
a0=+∞a0=+∞ size 12{ { {a} over {0} } "=+" infinity } {}, за (a>0)(a>0) size 12{ \( a>0 \) } {}
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size 12{ \( + infinity \) + \( + infinity \) "=+" infinity } {}
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size 12{ \( - infinity \) + \( - infinity \) = - infinity } {}
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size 12{ \( + infinity \) cdot \( + infinity \) "=+" infinity } {}
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size 12{ \( - infinity \) cdot \( - infinity \) "=+" infinity } {}
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size 12{ \( - infinity \) cdot \( - infinity \) "=+" infinity } {}
Изразите
00,±∞±∞,0⋅(±∞),(+∞)+(−∞)00,±∞±∞,0⋅(±∞),(+∞)+(−∞) size 12{ { {0} over {0} } ,~ { { +- infinity } over { +- infinity } } ,~0 cdot \( +- infinity \) ,~ \( + infinity \) + \( - infinity \) } {} не се определени и за нивно пресметување постојат постапки со кои се разрешува неопределеноста.
