SOHCAHTOA gives the three trigonometry ratios in a right-angled triangle: sine equals opposite over hypotenuse, cosine equals adjacent over hypotenuse, tangent equals opposite over adjacent. Label the sides from the marked angle, pick the ratio using the two sides you know and want, then solve.
SOHCAHTOA is the memory aid for the three trigonometric ratios in a right-angled triangle: Sin = Opposite/Hypotenuse, Cos = Adjacent/Hypotenuse, Tan = Opposite/Adjacent.
Labelling opposite and adjacent from the right angle rather than from the marked angle.
Leaving the calculator in radians. For GCSE it must be in degrees.
Untimed practice with worked answers. Every answer is a whole number. This extra activity does not count towards your daily progress.
Sin = Opposite ÷ Hypotenuse, Cos = Adjacent ÷ Hypotenuse, Tan = Opposite ÷ Adjacent. Label the sides from the angle you are using, then pick the ratio that uses the two sides you know or need.
Use sin⁻¹, cos⁻¹ or tan⁻¹ when you know two sides and want the angle. Use sin, cos or tan when you know an angle and one side and want another side.
Yes. The three trigonometric ratios are on the GCSE Maths formulae sheet for both tiers, but the exact values for 0°, 30°, 45°, 60° and 90° are not, so learn those. See the GCSE Maths formula sheet.
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