What is constructive induction and how is it used to solve recursive equations?

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Constructive induction is a method used to prove properties of recursive equations by making educated guesses about their solutions. In the given example, the recursive equation T(n) = T(⌈n/4⌉) + T(⌈2n/3⌉) + Θ(n) is analyzed to show that it falls within the complexity class Θ(n). However, the discussion highlights the importance of clearly defining Θ(n) to validate the proof, as the values of T(n) at specific points do not align with the general form of Θ(n). The complexity class Θ(n) represents functions that grow linearly, bounded above and below by constant multiples of n. Understanding these concepts is crucial for effectively applying constructive induction to solve recursive equations.
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Can someone explain this "constructive induction" needed to solve recursive equations?

For example, use "constructive induction" to show that the following is \Theta (n)

T(n) = 1 \leftrightarrow n = 1,2
T(n) = T\lceil n/4\rceil + T \lceil 2n/3\rceil + \Theta (n) \leftrightarrow n > 2
 
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Anyone? This is kinda urgent.
 
Dragonfall said:
Can someone explain this "constructive induction" needed to solve recursive equations?

For example, use "constructive induction" to show that the following is \Theta (n)

T(n) = 1 \leftrightarrow n = 1,2
T(n) = T\lceil n/4\rceil + T \lceil 2n/3\rceil + \Theta (n) \leftrightarrow n > 2

Since you haven't said what \Theta(n) is, I don't see how any method can "prove" that is \Theta(n).

Whatever \Theta(n) is, T(3) is definitely not equal to \Theta(3), it is equal to \Theta(3)+ 2.
 
\Theta (n) in the recurrence is "some function" in the complexity class \Theta (n).

The complexity class \Theta (n) is the intersection of O(n) and \Omega (n).
 
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