Recall from Lesson 1A that an important use of set theory is in computer science to verify that programs do what they are supposed to do. An extension of this idea is to use set theory to analyze Internet search strategies. This concept is examined in the next several pages of the lesson.

Read pages 42-44 Example 2 in your textbook, Principles of Mathematics 12 .

Complete the Your Turn question on page 44 related to word choice for internet searches.

Click here to verify your answers .

 

Someone left a backpack full of school books on a transit bus. The only identification is the name John Smith , so the bus driver took the backpack to the public school board office. The staff searched their database and learned that 84 students have this name. How can the staff narrow their search using search tools and other items in the backpack?

Staff could look at how many John Smiths were on that bus route or they could look at the books in the bag and see how many John Smiths are taking courses that use those books.

 

Maria is planning a winter ski holiday in the Canadian Rockies. Give four words or phrases that Maria might use to search for information on the Internet. Use set theory to explain how quotation marks and the word and could help her refine her search.

"Canadian Rockies" , "ski accommodations" , "weather forecast" , and "Whistler" are phrases that Maria could use to search for information on the Internet.

By combining two or more of these terms, Maria can search for the intersection of web pages related to these terms. For example, "ski accommodations" and "Canadian Rockies" is more likely to give her useful information for her trip than either of those terms on its own.