Artificial Intelligence: A Modern Approach
Artificial Intelligence: A Modern Approach
3rd Edition
ISBN: 9780136042594
Author: Stuart Russell, Peter Norvig
Publisher: Prentice Hall
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Chapter 3, Problem 28E
Program Plan Intro

Suboptimal solution:

  • Suboptimal heuristic search algorithms such as weighted A* and greedy best-first search are widely use to solve problems for which guaranteed optimal solutions are too expensive to obtain.
  • To guide their search, these algorithms rely on a heuristic function.
  • These algorithms are used because, when constructing the heuristics, the optimal search can fail when considering the suboptimal search.

Explanation of Solution

Proof:

  • As given in the problem, suppose h(n)h*(n)+c and let G2 be a goal that is optimal more than c. That is g(G2)>C*+c.
  • Consider any node n on a path to an optimal goal. Here,

    f(n)=g(n)+

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