Lesson 2

1. Complete “Check Your Understanding” question 2.b. on page 138 of your textbook. Answer
   
   
2. Complete “Practising” questions 3.d., 3.e., 4, 7, and 8 on pages 139 and 140 of your textbook. (Note: In question 7, you are asked to solve a triangle. This means that you must give the measures of all three sides and all three angles.) Answer

In the Discover section of this lesson, you used the Sine Law Explorer to see a visual justification of the sine law. A mathematician would say that you used “inductive reasoning” to infer that the sine law is true for all triangles. In order to prove that the sine law is always true, you must use a process called “deductive reasoning.”

Read how Ben used deductive reasoning to prove the sine law in “Investigate the Math” on pages 132 and 133 of your textbook.

Try This 3

You may choose to work on your own or with a partner to improve upon Ben’s proof. Answer questions A to F on the bottom of page 133 of your textbook.

Place a copy of your responses in your course folder.