Trig ratios

Sine (sin), Cosine (cos), and Tangent (tan).

It is a mnemonic to remember the definitions of the sine, cosine, and tangent ratios: Soh = sin = opposite/hypotenuse, Cah = cos = adjacent/hypotenuse, Toa = tan = opposite/adjacent.

You can use the sine ratio: height = distance from the object * sin(angle of elevation).

The opposite side = 10 * sin(30°) = 10 * 0.5 = 5.

The ratios of the lengths of the sides are constant for given angles, which defines the trigonometric functions.

Use the tangent ratio: angle = arctan(opposite/adjacent).

cos(45°) = √2/2 or approximately 0.707.

Tangent is the ratio of the length of the opposite side to the length of the adjacent side: tan(θ) = opposite/adjacent.

Identify the known sides and the angle, then use the appropriate trigonometric ratio (sin, cos, or tan) to solve for the unknown side.

sin(90°) = 1.