SOHCAHTOA Trainer
Name the sides of a right-angled triangle, choose sin, cos or tan, then find a missing side or angle to 1 decimal place.
About this activity
Trigonometry one step at a time: students name the hypotenuse, opposite and adjacent from the marked angle, choose the ratio for the two sides in a question, then find a missing side (one you multiply by, then one you divide by) and a missing angle with the inverse functions. Each answer is checked straight away, with the working shown. The triangles, angles and lengths change every time. A calculator in degrees mode is needed for the last three parts.
How to use SOHCAHTOA Trainer
- SOHCAHTOA Trainer is a free Maths activity for Years 9 to 11 that takes about 12 minutes. Try it on this page on a computer, tablet or phone: there’s nothing to download.
- In a lesson, choose Show on the board to play it together as a class.
- To set it for a class, a teacher shares it and gets a code: students type the 6-digit code at lycolearn.co.uk/join with their first name and the first letter of their surname (no accounts needed), and their scores come back to the teacher.
Students will
- Name the hypotenuse, opposite and adjacent sides from an angle
- Choose sin, cos or tan for the two sides in a question
- Find a missing side or angle in a right-angled triangle
Teaching tips
- The first two parts need no calculator, so they work as a starter on their own: set it with 5 questions.
- Students who get the sides wrong usually label them from the right angle instead of the marked angle: the first part trains this.