1. Lesson 5

Mathematics 20-2 M5 Lesson 5

Module 5: Radicals

 

Lesson 5: Rationalizing Radical Expressions

 
Focus
 

This collage shows two views of cliff divers in Acapulco, Mexico.

diver on cliff: Medioimages/Photodisc/Thinkstock; diver in air: Brand X Pictures/Thinkstock

La Quebrada Cliff Divers at Acapulco, Mexico, are trained divers who entertain tourists with spectacular dives.

 

Trained professional cliff divers or Clavadistas at Acapulco, Mexico, leap out from the cliff face and plunge 35 m into a shallow gorge below. That is comparable to diving off a 12-storey building. In the gorge, the water depth varies from 2 m to 5 m, depending on the wave action. Timing a jump is essential in order to be sure that the water is deep enough that the diver does not hit the rocky ocean floor.

 

In order to be as safe as possible when cliff jumping, divers make sure ahead of time that the water is deep enough and there are no hidden ledges or rocks in the water below them. A formula to calculate the time it takes for the diver to hit the water is

 

 

In this lesson you will learn to simplify fractional radicals by writing them without a radical in the denominator.

 

This lesson will help you answer the following inquiry questions:

  • How do you simplify a fractional radical by rationalizing the denominator?

  • How do you explain, using examples, the rules for writing positive and negative roots?
Assessment

All assessment items you encounter need to be placed in your course folder.

 

 

course folder

Save a copy of the Lesson 5 Assignment to your course folder. You will receive more information about how to complete the assignment later in this lesson.

 

Materials and Equipment
  • calculator