# Trigonometry

Updated May 2018. Click title lines to see additional content.

#### Trigonometry: use in finding heights

These excellent materials were designed at Leeds Metropolitan University and are excellent for seeing trigonometry in real use.- Teacher/pupil task sheet with Clinometer template for angle measuring.
- Theodolite poster - how to use to find a height.
- File showing how to use theodolite: 15 pages includes answers.
- Another theodolite example to find height of a wall.
- The related YouTube channel (here) has 5 videos including one that shows how to make the clinometer (here).
- Instructions and template for making a trig-wheel.

#### Trigonometry: ship's course

Another example of a real use of trigonometry (to find a ship's course) comes from Maths at Work and includes video. This is on the NCETM site, so you may need to login#### Trigonometry: height of tower at British Museum

The British Museum has a KS3 challenge to find the height of a tower in its great court (February 2016). BM KS3 Maths Challenge (includes other ideas as well).#### Trigonometry: Practical lesson

- Create clinometers or borrow theodolites. Borrow long tapes from PE, use metre rules or laser distance measures.
- Go outside and have pupils stand different distances away from eg the school building (if you can).
- Measure distance from school building, use clinometer to find angle, take distance of height of clinometer above ground level.
- Have each pupil calculate height of building and then use mean, mode or median to decide 'height'.
- Consider rounding, accuracy, think about which errors of measurement have the biggest impact.
- Think about other ways to find the height of the building - could any of these be more accurate?
- Find true height of building from building plans!
- With brick buildings finding the height of e.g. 10 layers of bricks is usually the most accurate method.

#### SIne Wave

Great fun making sine wave from spaghetti.

#### Unit circle: Geogebra file

This GeoGebraTube file, diagram below, shows movement around unit circle as well as motion of vertical component.