Trigonometry Monday, 18 February 2019

An introduction to Trigonometry A Power point for those who have never met trigonometry before.

An introduction to Trigonometry Opposite A

An introduction to Trigonometry Hypotenuse Opposite A

An introduction to Trigonometry Hypotenuse Opposite A Adjacent

Label each of the following triangles (i) (ii) (iii) Example Label each of the following triangles (i) (ii) (iii) g d A f b a h i e A A c

Example For the triangle below Write down the lengths of the opposite and hypotenuse sides Work out the ratio Opposite = 8cm Hypotenuse = 12cm 12cm 8cm 41.8° c) Now work out the sin of 41.8° using the calculator Sin 41.8°=0.6665

Right-angled Trigonometry Opp Hyp A Adj

Example Work out the lettered length in the triangle given below, giving your answer to 1 decimal place. 8 cm a 25°

Example Work out the lettered length in the triangle given below, giving your answer to 1 decimal place. 15 m 48° b

Example Work out the lettered length in the triangle given below, giving your answer to 2 decimal place. 15° 37 cm b

Example Work out the length of AB in the triangle given below, giving your answer to 2 decimal place. A 56° C B 7 m

Example For the triangle below Write down the lengths of the Adjacent and hypotenuse sides Work out the ratio 12cm Adjacent = 7cm Hypotenuse = 12cm 54.3° 7cm c) Now work out the cos of 54.3° using the calculator cos 54.3°=0.5835

Right-angled Trigonometry Opp Hyp A Adj

Example Work out the lettered length in the triangle given below, giving your answer to 1 decimal place. 10 cm 31° a

Example Calculate the length of PQ in the triangle PQR P R 52 cm 32 Q

Example Calculate the length XY in the triangle XYZ X Y 59 4.6 cm Z

Right-angled Trigonometry Opp Hyp A Adj

Example Work out the lettered length in the triangle given below, giving your answer to 1 decimal place. 4 cm 27° a

Example Calculate the length XZ in the triangle XYZ, giving your answer correct to 3 significant figures. 4.6 cm Y Z 38 X

Example Work out the length of AC in the triangle given below, giving your answer to 2 decimal place. A 56° C B 7 m