Day 2: Primary Trigonometric Ratios Unit 8: Trigonometry

Learning Goals To be able to use the primary trigonometric ratios

Labeling a Triangle Vertices/angles are ALWAYS denoted with a capital letter Sides are ALWAYS denoted with a lower case letter The side and angle that are across from each other are ALWAYS the same letter

Labeling a Triangle

Primary Trig Ratios Activity You need a ruler and a protractor You may work in partners You have 15 minutes

Primary Trig Ratios 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 ℎ𝑦𝑝𝑜𝑡𝑒𝑛𝑢𝑠𝑒 = sin 𝑥 𝑎𝑑𝑗𝑎𝑐𝑒𝑛𝑡 ℎ𝑦𝑝𝑜𝑡𝑒𝑛𝑢𝑠𝑒 = cos 𝑥 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 𝑎𝑑𝑗𝑎𝑐𝑒𝑛𝑡 = tan 𝑥

SOHCAHTOA

Evaluate. c) tan 15° a) sin 60° =0.8660 b) cos 45° =0.7071 =0.2679 What do these values represent? The ratio of the two sides NOT the value of any one side NOT the value of the angle b) cos 45° =0.7071 c) tan 15° =0.2679

Evaluate. a) sin 𝐴 =0.5 𝐴= sin −1 0.5 𝐴=30° What do these values represent? The values of angles A, B and C b) cos 𝐵 = 3 10 𝐵= cos −1 3 10 𝐵=73° c) tan 𝐶 =1.4239 𝐶= tan −1 1.4239 𝐶=55°

List the primary trig ratios for angle A. sin 𝐴 = 4 𝑐 cos 𝐴 = 6 𝑐 tan 𝐴 = 4 6 hypotenuse opposite A adjacent

List the primary trig ratios for angle B. sin 𝐵 = 6 𝑐 cos 𝐵 = 4 𝑐 tan 𝐵 = 6 4 B hypotenuse adjacent opposite

Success Criteria I CAN properly label a right triangle and set up the primary trigonometric ratios

To Do… Worksheet Check the website daily for updates, missed notes, assignment solutions www.mrsmccrum.weebly.com