Right triangle trigonometry

SOHCAHTOA Calculator

SOHCAHTOA is a memory aid for sine, cosine, and tangent in right triangles: sine uses opposite over hypotenuse, cosine uses adjacent over hypotenuse, and tangent uses opposite over adjacent.

Quick answer: SOHCAHTOA is a memory aid for sine, cosine, and tangent in right triangles: sine uses opposite over hypotenuse, cosine uses adjacent over hypotenuse, and tangent uses opposite over adjacent. For exact academic decisions, verify the result with your school, registrar, adviser, or the official office handling the requirement.

What SOHCAHTOA means

SOH means sin(theta)=opposite/hypotenuse. CAH means cos(theta)=adjacent/hypotenuse. TOA means tan(theta)=opposite/adjacent.

When to use it

Use it only for right triangles when you know one acute angle and one side, or when you know two sides and need an angle.

Study tip

Label the hypotenuse first, then identify opposite and adjacent based on the angle you are using.

Frequently Asked Questions

Does SOHCAHTOA work on any triangle?

No. It is for right triangles.

What if I know two sides?

Use inverse sine, cosine, or tangent depending on which sides are known.