1. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. The Trigonometric ratios: …there are three trig ratios opposite adjacent hypotenuse opposite hypotenuse Sine ratio = adjacent hypotenuse Cosine ratio = opposite adjacent Tangent ratio =

2. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find angle ABC. opp hyp Sin = adj hyp Cos = opp adj Tan = A B C 8cm 12cm x opp hyp Label the sides.Choose a ratio. sin x 0 = opposite hypotenuse sin x 0 = 8 12 x0x0 = 0.6666 x = 42 0 sin sin -1

3. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find angle ABC. opp hyp Sin = adj hyp Cos = opp adj Tan = A B C 18cm 10cm x Label the sides. hyp adj Choose a ratio. cos x 0 = adjacent hypotenuse cos x 0 = 10 18 x0x0 = 0.5555 x = 56 0 cos cos -1

4. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find the length of side BC. opp hyp Sin = adj hyp Cos = opp adj Tan = A B C 64 0 15cm x Label the sides. adj hyp Choose a ratio. cos 64 0 = adjacent hypotenuse cos 64 0 = x 15 cos 64 0 = x 15 x x 6.6cm = x

5. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find the length of side AB. opp hyp Sin = adj hyp Cos = opp adj Tan = x Label the sides. adj opp Choose a ratio. A B C 11cm 58 0 tan 58 0 = opposite adjacent tan 58 0 = x 11 tan 58 0 = x 11 x x 17.6cm = x

6. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find the length of side AB. opp hyp Sin = adj hyp Cos = opp adj Tan = A B C 7cm 27 0 x Label the sides. opp hyp Choose a ratio. sin 27 0 = opposite hypotenuse sin 27 0 = 7 x = 7 x = x = 15.4cm

7. Trigonometry Lesley Hall @ Soar Valley College Objective: To use trigonometric ratios to find sides and angles in right-angled triangles. Find the length of side BC. opp hyp Sin = adj hyp Cos = opp adj Tan = A C B 5.8cm 39 0 x Label the sides. opp adj Choose a ratio. tan 39 0 = opposite adjacent tan 39 0 = 5.8 x tan 39 0 = 5.8 x = x = 7.2cm