Show that 100n lg n50n n log n You have to use the formal d
Show that 100n lg n+50n = (n log n). You have to use the formal denition of (you must and specify c1, c2, n0).
Solution
Answer:
We have given
f(n) = 100nlogn +50n , g(n) = nlogn
We know theta definition
c1 * nlogn < = 100nlogn +50n < = c2*nlogn
let c1 = 1 , c2 = 1000
nlogn < = 100nlogn + 50n < = 1000 *nlogn
Now calculate :
nlogn < = 100nlogn + 50n
nlogn - 100nlogn = 50n
-99nlogn = 50n
-99nlogn -50n = 0
-99logn -50 = 0
-99logn = 50
n = 2
100nlogn +50n < = 1000*nlogn
100nlogn +50n - 1000nlogn = 0
100logn - 1000logn = 50
2logn -20logn = 1
logn(2 -20) = 1
logn * -18 = 1
logn = 1/18
n = e^1/18 = 1.057
Therefore 100nlogn +50 = theta(nlogn) at c1 = 1 , n = 1000 , n = 2

