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Properties-of-Asymptotic-Notations

General properties

if f(n) is O(g(n)),then af(n) is  O(g(n))if \space f(n)\space is\space O(g(n)), then\space a * f(n)\space is\space\space O(g(n))

eg:f(n)=2n2+5,O(n)=n2 if 7(2n2+5)=14n2+35, then  O(n) also O(n2)eg: f(n) = 2n^2+ 5, O(n) = n ^2 \space if \space 7 * (2n^2 + 5) = 14n^2 + 35, \space then \space\space O(n) \space also \space O(n^2) if f(n) is Ω(g(n)),then af(n) is  Ω(g(n))if \space f(n)\space is\space \Omega(g(n)), then\space a * f(n)\space is\space\space \Omega(g(n))

eg:f(n)=2n2+5,Ω(n)=n2 if 7(2n2+5)=14n2+35, then  Ω(n) also Ω(n2)eg: f(n) = 2n^2+ 5, \Omega(n) = n ^2 \space if \space 7 * (2n^2 + 5) = 14n^2 + 35, \space then \space\space \Omega(n) \space also \space \Omega(n^2)

Reflective properties

if f(n) is given,then f(n)  is  O(f(n))if \space f(n)\space is\space given, then \space f(n) \space\space is\space\space O(f(n)) eg:f(n)=n2,O(n)=n2=f(n)eg: f(n) = n^2, O(n) = n ^2 = f(n)

Transitive properties

if f(n) is  O(g(n)),and g(n) is O(h(n)),then f(n)=O(h(n))if \space f(n)\space is\space\space O(g(n)), and\space g(n) \space is\space O(h(n)), then \space f(n)= O(h(n)) eg:f(n)=n g(n)=n2 h(n)=n3 n is O(n2),n2 is O(n3),then n is O(n3)eg: f(n) = n \space g(n) = n^2 \space h(n) = n ^3 \space \therefore n\space is \space O(n^2), n^2\space is \space O(n^3), then\space n\space is \space O(n^3)

Symmetric properties

if f(n) is  Θ(g(n)),then g(n)=Θ(f(n))if \space f(n)\space is\space\space \Theta(g(n)), then \space g(n)= \Theta(f(n)) $eg: f(n) = n^2 \space g(n) = n^2 \space \because f(n)=\Theta(n^2) \therefore g(n)=\Theta(n^2) $

Transpose Symmetric properties

if f(n) is  O(g(n)),then g(n)=Ω(f(n))if \space f(n)\space is\space\space O(g(n)), then \space g(n)= \Omega(f(n)) $eg: f(n) = n \space g(n) = n^2 \space \because n\space is\space O(n^2), then \space n^2 \space is \space \Omega(n) $

Properties && Asymptotic Notations

if f(n) =  O(g(n)),and f(n)=Ω(g(n))if \space f(n)\space =\space\space O(g(n)), and \space f(n)= \Omega(g(n)) g(n)<= f(n)<=Ω(g(n)) θf(n)=g(n)\therefore g(n)<= \space f(n)<=\Omega(g(n)) \space\therefore \theta f(n)= g(n)

Properties && Asymptotic Notations2

if f(n) =  O(g(n)),and d(n)=O(e(n)) thenf(n)+d(n)=O(max(g(n),e(n)))if \space f(n)\space =\space\space O(g(n)), and \space d(n)= O(e(n)) \space then f(n) + d(n) = O(max(g(n),e(n))) eg:f(n)=n2=O(n) d(n)=n=O(n2) f(n)+d(n)=n2+n=O(n2)eg: f(n)= n^2 = O(n) \space d(n)=n=O(n^2) \space\therefore f(n)+d(n)=n^2+n=O(n^2)

Properties && Asymptotic Notations3

if f(n) =  O(g(n)) and d(n)=O(e(n)) thenf(n)d(n)=O(g(n)e(n)))if \space f(n)\space =\space\space O(g(n))\space and \space d(n)= O(e(n)) \space then f(n) * d(n) = O(g(n)*e(n)))