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ARE ANGLES IMPORTANT IN TRIGONOMETRY

It is an intriguing question as to whether angles are important in trigonometry. This needs to be answered with the help of basic mathematical evidence.

An angle may be defined as the joining of two rays that share a common point of concurrence. The rays are called the ideas of their angle, and the common point of concurrence is known as the vertex of the angle. It needs to be taken into account that the measurement of an angle is basically the measurement of the space between the rays. The question as to whether angles are important in trigonometry has been cited to reach a practically acceptable conclusion. 

Explanation of basic trigonometric formula 

Considering the basics of geometry, and majorly the basic angles, there are six types of angles such as “reflex angles, acute angles, straight angles, full rotation, right angles, and obtuse angles”. In order to understand the source of “trigonometric formulas” it is necessary to understand the structure of a triangle with the right angle. The sides that are adjacent to the right angle are termed the legs, whereas the side opposite the right angle are called the legs. Angels play an important role in the formation of “trigonometric formulas”. These are sets of a wide range of formulas that involve trigonometric identities. Trigonometric formulas can be widely used to solve complex problems associated with an alignment of angles of a triangle with the right angle. It needs to be considered that there are certain trigonometric functions that constitute the trigonometric formulas, such trigonometric functions are “cosine, secant, sine, cotangent and tangent.” 

Trigonometric angles may be defined as the angles that are derived by the ratios of the trigonometric functions. The study of the relationship of the arrangement of triangles is the basis of trigonometry. The range of angle varies from 0 to 360 degrees. The major angles in trigonometry are “360 degree, 45 degree, 270°, 30°, 0°, 60°, 180° and 90°”. There are some common angles that are used to solve trigonometric problems such as “0°, 30°, 45, 60 and 90”. Therefore, the students of mathematics are required to memorize the values associated with trigonometric ratios. There are some angles that can be considered as positive or negative anglers. When an ankle is formed in a clockwise direction from the very beginning point in an X-Y plane, it is considered cf to be positive whereas, when the angle is formed in a direction that is clockwise from the starting point, then it is termed as negative angle.  Radians and degrees are the basic measurements to determine angles in trigonometry. 

Use of trigonometric formulas 

The Trigonometric angles are formed on the basis of the four quadrants of a circle the types of trigonometric angles are supplementary angles, Anti-supplementary angles, complementary angles, and opposite angles. 

The trigonometric functions and identities are derived on the basis of triangle with the right angle:

“Sin= Opposite side/ Hypotenuse”

“Cost= Adjacent side/ Hypotenuse”

“Tan = Opposite Side/ Adjacent side”

“Sect = Hypotenuse/ Adjacent side”

“Cosec θ = Hypotenuse/ Opposite side”

“Cot θ= Adjacent side/ Opposite side”

There are certain reciprocal identities that play an important role in the formation of trigonometric formulas. The reciprocal identities are basically the reciprocal. “There are six main trigonometric functions such as sine, cosine, cosecant, secant, cotangent, tangent.” However, it needs to be considered that these reciprocal identities are not similar to inverse trigonometric functions. 

The reciprocal identities are as follows:

“Cosecθ = 1/ Sinθ”

“Secθ = 1/ cosθ”

“Cotθ = 1/ tanθ”

“Sinθ = 1/ cosecθ”

“Cos θ = 1/ secθ”

“Tanθ = 1/ cotθ”

The interesting fact about these identities and reciprocal identities is that these are derived from a triangle with the right angle. Considering the height, base side of the right angle it is possible to find the cosine, sine, secant, cosecant, and cotangent values just by applying the trigonometric formulas. The reciprocal trigonometric ideas can be formed by using the trigonometric functions. 

The Pythagorean Theorem or the formula associated with it is the foundation of determining the trigonometric formulas from a triangle that consists of a right angle. It needs to be taken into account that the six trigonometric functions are similar to its evaluated co-function at the complementary angle. The values of “Sinθ” in “0”, “30”, “45”, “60”, and “90 degrees” are “0”, “½”, “1/√2”, “√3/2”, and “1” respectively. In the case of “Cosθ” the values under “0”, “30”, “4”’, “60”, and “90 degrees” are as follows “1”, “√3/2”, “/√2”, “½” , and “0” respectively. The values of “tanθ” in “0”, “30”, “45”, “60”, and “90 degrees” are “0”, “1/√3”, “1”, “√3” , and an unidentified value respectively. “Cosecθ” represents “0”, “30”, “45”, “60”, and “90 degrees” in values such as an “unidentified value”, “2”, “√2”, “2/√3” and “1” respectively. “Secθ under” “0”, “30”, “45”, “60”, and “90 degrees” has a value of “1”, “2/√3”, “√2”, “2”, and an “unidentified value”. Lastly, there is “Cotθ” which has an “unidentified value” for “0”, “√3” for “30”, “1” for “45”, and “0” for “90 degrees.”

Conclusion 

The above discussion clearly states that the angles serve as pillars or foundation of trigonometry. Trigonometry is basically the relation between the sides and angles of triangles, therefore, the trigonometric formulas and identities are derived on the basis of the functions of angles. The above discussion and analysis clearly indicates that trigonometric formulas deal with the specified functions of angles, and their applications with respect to trigonometric calculation.

 
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Frequently asked questions

Get answers to the most common queries related to the NDA Examination Preparation.

What are the basic trigonometric identities?

 Ans) “Cos2θ + Sin2θ” = “1”

“1+ tan2θ” = “Sec2θ”

“1+ cot2θ” =  “Cosec2θ”

What is the trigonometric function for tan in a triangle with the right angle?

 Ans) “Sinθ/Cosθ”

What is the trigonometric value for “tan 45°”?

Ans) 1

What are the six main functions of trigonometry?

Ans) The six main trigonometric functions are “sine”, “cotangent”, “cosine”, “cosecant”, “secant”, and  “tangent”....Read full