Answer:
There are six trigonometric ratios defined in the right triangles. Below you will find their definitions and how to calculate them.
Explanation:
The six trigonometric ratios are sine, cosine, tangent, cosecant, secant, and cotangent.
The symbols used for them are:
- sine: sin
- cosine: cos
- tangent: tan
- cosecant: csc
- secant: sec
- cotangent: cot
The trigonometric ratios are defined as the ratio of the sides in right triangles.
In a right triangle the two sides opposite to the accute angles are called legs, and the side opposite to the right angle (the larger side) is called hypotenuse.
The sine of an angle is the ratio of the opposite leg to the angle to the hypotenuse. So, you find the sine by doing the quotient of the length of the opposite leg to the angle and the length of the hypotenuse.
- sine (angle) = length of the opposite leg / length of the hypotenuse.
The cosine of an angle is the ratio of the adjacent leg to the angle to the hypotenuse. So, you find the cosine by doing the respective division:
- cosine (angle) = length of the adjacent leg / length of the hypotenuse
The tangent of an angle is the ratio of the sine to the cosine of the same angle. So, you find it either by dividing sine by cosine or by dividing the length of the opposite angle by the length of the adjacent angle.
- tangent (angle) = sine (angle)/ cosine (angle) = opposite leg / adjacent leg.
Cosecant is the inverse of the sine, secant is the invers of the cosine, and cotangent is the inverse of the tangent. So, you find them by these equations:
- cosecant (angle) = 1 / sine (angle) = hypotenuse / opposite leg
- secant (angle) = 1 / cosine (angle) = hypotenuse / adjacent leg
- cotangent (angle) = 1 tangent (angle) = adjacent leg / opposite leg.
