How to Calculate Sine 30

Right Triangle

Sine is a mathematical formula used primarily in trigonometry. Sine uses a right triangle. A right triangle has three sides and a 90 degree angle. The sides are known as the hypotenuse, opposite and adjacent. The formula for sine of an angle equals opposite over the hypotenuse. The sine of 30 degrees will always be 0.5.

Things You'll Need

• Ruler

Instructions

1. Determine the length of the hypotenuse of the triangle with a ruler in the required measurement standard. The hypotenuse is the longest side. As an example, the hypotenuse of a given triangle with a 30 degree angle is 2 inches.

2. Determine the length of the opposite side with a ruler in the required measurement standard. The opposite side is the side directly opposite of the 30 degree angle. In the example, the opposite side of a triangle with a 30 degree angle is 1 inch.

3. Divide the opposite side by the hypotenuse. In the example, sin 30 equals 1 divided by 2 equals 0.5.

References

• Math Is Fun: Sine, Cosine, Tangent
• CSG Network: Right Triangle Angle and Side Calculator