Sine (sin), Cosine (cos), and Tangent (tan) are fundamental trigonometric functions that describe relationships between the angles and sides of a right-angled triangle. These are the basic ratios of Trigonometry that are used to study the relationship between the angles and respective sides of a triangle. These ratios are initially defined on a Right Angled Triangle using Pythagoras Theorem. Sin, cos, and tan have extensive applications in fields like physics, engineering, and computer graphics. In this article, we will explore the values of these trigonometric functions, their significance, and how they are used in real-world scenarios.
Sine (sin), cosine (cos), and tangent (tan) in Trigonometry
Let's understand Sin, Cos, and Tan in trigonometry using formulas and examples.
A triangle that has one angle of 90° is called a right-angled triangle. It has sides called the base, perpendicular (height), and hypotenuse. The right-angled triangle follows the Pythagoras theorem.
| Term | Definition |
|---|
| Base | The side which contains the angle is called the base of the triangle. |
| Perpendicular | The side which forms 90° with the base is called perpendicular or the height of the triangle. |
| Hypotenuse | The longest side of the triangle is called the hypotenuse of the triangle. |
Sin, Cos, and Tan are the ratios of the sides of any right-angled triangle. In the right-angled triangle ABC given above for angle C the Sin, Cos, and Tan are,
- Sin C = Perpendicular / Hypotenuse = AB / CA
- Cos C = Base / Hypotenuse = BC / CA
- Tan C = Perpendicular / Base = AB / BC
Sin, Cos, and Tan functions are defined as the ratios of the sides (opposite, adjacent, and hypotenuse) of a right-angled triangle. The formulas of any angle θ sin, cos, and tan are:
- sin θ = Opposite/Hypotenuse
- cos θ = Adjacent/Hypotenuse
- tan θ = Opposite/Adjacent
There are three more trigonometric functions that are reciprocal of sin, cos, and tan which are cosec, sec, and cot respectively, thus
- cosec θ = 1 / sin θ = Hypotenuse / Opposite
- sec θ = 1 / cos θ = Hypotenuse / Adjacent
- cot θ = 1 / tan θ = Adjacent / Opposite
Trigonometric Functions
The Trigonometric functions are also called trigonometric ratios. There are three basic and important trigonometric functions: Sine, Cosine, and Tangent.
- The sine trigonometric function is written as sin, cosine as cos, and tangent as tan in trigonometry.
- There are three more trigonometric functions: cosec, sec, and cot, which are the reciprocals of the sin, cos, and tan.
- These functions can be evaluated for the right-angled triangle.
Let a right-angled triangle with base b, perpendicular p, and hypotenuse h form θ angle with the base. Then, the trigonometric functions are given by:
Trigonometric Functions | Formula of Trigonometric Functions |
|---|
sin θ | - sinθ = perpendicular/hypotenuse
- sinθ = p / h or θ = sin-1( p / h)
|
cos θ | - cosθ = base/hypotenuse
- cosθ = b / h or θ = cos-1( b / h)
|
tan θ = sin θ/cos θ | - tanθ = perpendicular/base
- tanθ = p / b or θ = tan-1( p / b)
|
cosecθ = 1/sin θ | - cosecθ = hypotenuse/perpendicular
- cosecθ = h / p or θ = cosec-1(h / p)
|
secθ = 1/cos θ | - secθ = hypotenuse/ base
- secθ = h / b or θ = sec-1(h / b)
|
cotθ = 1/tan θ | - cotθ = base/perpendicular
- cotθ = b / p or θ = cot-1( b / p)
|
Trick to Remember Sin, Cos, Tan Ratio
Statement to remember | Some people have curly black hair to produce beauty |
|---|
| Some people have | sinθ (some) = perpendicular(people)/hypotenuse(have) |
| curly black hair | cosθ (curly)= base(black)/hypotenuse(hair) |
| to produce beauty | tanθ (to)= perpendicular(produce)/base(beauty) |
Sin Cos Tan Values
Sin, Cos, and Tan values are the value of specific angles of a right-angled triangle. In trigonometry formulas, the values of Sin, Cos, and Tan are different for different values of angles in the triangle. For each specific angle, the value of sin, cos, and tan are the fixed ratio between the sides.
Sin Cos Tan Values Table
In trigonometry, we have basic angles of 0°, 30°, 45°, 60°, and 90°. The below Trigonometric table gives the value of trigonometric functions for basic angles:
| θ | 0° | 30° | 45° | 60° | 90° |
|---|
| sin | 0 | 1/2 | 1/√2 | √3/2 | 1 |
|---|
| cos | 1 | √3/2 | 1/√2 | 1/2 | 0 |
|---|
| tan | 0 | 1/√3 | 1 | √3 | ∞ |
|---|
| cosec | ∞ | 2 | √2 | 2/√3 | 1 |
|---|
| sec | 1 | 2/√3 | √2 | 2 | ∞ |
|---|
| cot | ∞ | √3 | 1 | 1/√3 | 0 |
|---|
Sin, Cos, Tan Chart
The positivity or negativity of trigonometric ratios depends on the quadrant in which the angle lies. The following chart defines the positivity and negativity for all trigonometric ratios in each quadrant breakdown:
- The sine and cosecant functions are positive in the first and second quadrants and negative in the third and fourth quadrants.
- The cosine and secant functions are positive in the first and fourth quadrants and negative in the second and third quadrants.
- The tangent and cotangent functions are positive in the first and third quadrants and negative in the second and fourth quadrants.
| Degrees | Quadrant | Sign of sin | Sign of cos | Sign of tan | Sign of cosec | Sign of sec | Sign of cot |
|---|
| 0° to 90° | 1stquadrant | +(positive) | +(positive) | +(positive) | +(positive) | +(positive) | +(positive) |
| 90° to 180° | 2ndquadrant | +(positive) | –(negative) | –(negative) | +(positive) | -(negative) | -(negative) |
| 180° to 270° | 3rd quadrant | –(negative) | -(negative) | +(positive) | -(negative) | -(negative) | +(positive) |
| 270° to 360° | 4th quadrant | –(negative) | +(positive) | -(negative) | -(negative) | +(positive) | -(negative) |
Reciprocal Identities
A cosecant function is the reciprocal function of the sine function and vice versa. Similarly, the secant function is the reciprocal function of the cosine function, and the cotangent function is the reciprocal function of the tangent function.
- sin θ = 1/cosec θ
- cos θ = 1/sec θ
- tan θ = 1/cot θ
- cosec θ = 1/sin θ
- sec θ = 1/cos θ
- cot θ = 1/tan θ
Pythagorean Identities
Pythagoras Identities of trigonometric functions are:
- sin2θ + cos2θ = 1
- sec2θ – tan2θ = 1
- cosec2θ – cot2θ = 1
Negative Angle Identity
The negative angle of a cosine function is always equal to the positive cosine of the angle, whereas the negative angle of the sine and tangent function is equal to the negative sine and tangent of the angle.
- sin (– θ) = – sin θ
- cos (– θ) = cos θ
- tan (– θ) = – tan θ
Also, Check
Let's solve some example questions on the Sin Cos Tan Values.
Example 1: The sides of the right-angled triangle are base = 3 cm, perpendicular = 4 cm, and hypotenuse = 5 cm. Find the value of sin θ, cos θ, and tan θ.
Solution:
Given that,
Base (B) = 3 cm,
Perpendicular (P)= 4 cm
hypotenuse (H) = 5 cm
From the trigonometric functions formula:
sinθ = P/H = 4/5
cosθ = B/H = 3/5
tanθ = P/H = 4/3
Example 2: The sides of the right-angled triangle are base = 3 cm, perpendicular = 4 cm, and hypotenuse = 5 cm. Find the value of cosecθ, secθ, and cotθ.
Solution:
Given that, Base(b) = 3 cm, Perpendicular (p)= 4 cm and hypotenuse(h) = 5 cm
From the trigonometric functions formula:
cosecθ = 1/sinθ = H / P = 5/4
secθ = 1/cosθ = H / B= 5/3
cotθ = 1/tanθ = B / P = 3/4
Example 3: Find θ if the base = √3 and perpendicular = 1 of a right-angled triangle.
Solution:
Since, the perpendicular and base of the right-angled triangle is given so tan θ is used.
tan θ = perpendicular/ base
tan θ = 1/√3
θ = tan-1(1/√3) [from trigonometric table]
θ = 30°
Example 4: Find θ if the base = √3 and hypotenuse = 2 of a right-angled triangle.
Solution:
Since the base and hypotenuse of the right-angled triangle are given so cosθ is used.
cos θ = base / hypotenuse
cos θ = √3/2
θ = cos-1(√3/2) [from trigonometric table]
= 30°
Example 5: Find the value of x if sin(x) = 0.5 and 0° ≤ x ≤ 180°.
Solution:
Given sin(x) = 0.5
We know that sin(30°) = 0.5.
In the first quadrant, x = 30°.
In the second quadrant, sin(180° - 30°) = sin(150°), so x = 150°.
Therefore, x = 30° or 150°.
Example 6: If tan(θ) = 1 and 0° ≤ θ ≤ 360°, find all possible values of θ.
Solution:
Given tan(θ) = 1
We know that tan(45°) = 1 and tan(225°) = 1.
Therefore, θ = 45° or 225° (since tangent is positive in the 1st and 3rd quadrants).
Conclusion
Sin, Cos, and Tan values is essential for mastering trigonometry and solving problems involving right-angled triangles. These trigonometric ratios form the foundation for various applications in fields like physics, engineering, and architecture. By knowing the key values and how to apply them in different contexts
Similar Reads
Maths Mathematics, often referred to as "math" for short. It is the study of numbers, quantities, shapes, structures, patterns, and relationships. It is a fundamental subject that explores the logical reasoning and systematic approach to solving problems. Mathematics is used extensively in various fields
5 min read
Basic Arithmetic
What are Numbers?Numbers are symbols we use to count, measure, and describe things. They are everywhere in our daily lives and help us understand and organize the world.Numbers are like tools that help us:Count how many things there are (e.g., 1 apple, 3 pencils).Measure things (e.g., 5 meters, 10 kilograms).Show or
15+ min read
Arithmetic OperationsArithmetic Operations are the basic mathematical operations—Addition, Subtraction, Multiplication, and Division—used for calculations. These operations form the foundation of mathematics and are essential in daily life, such as sharing items, calculating bills, solving time and work problems, and in
9 min read
Fractions - Definition, Types and ExamplesFractions are numerical expressions used to represent parts of a whole or ratios between quantities. They consist of a numerator (the top number), indicating how many parts are considered, and a denominator (the bottom number), showing the total number of equal parts the whole is divided into. For E
7 min read
What are Decimals?Decimals are numbers that use a decimal point to separate the whole number part from the fractional part. This system helps represent values between whole numbers, making it easier to express and measure smaller quantities. Each digit after the decimal point represents a specific place value, like t
10 min read
ExponentsExponents are a way to show that a number (base) is multiplied by itself many times. It's written as a small number (called the exponent) to the top right of the base number.Think of exponents as a shortcut for repeated multiplication:23 means 2 x 2 x 2 = 8 52 means 5 x 5 = 25So instead of writing t
9 min read
PercentageIn mathematics, a percentage is a figure or ratio that signifies a fraction out of 100, i.e., A fraction whose denominator is 100 is called a Percent. In all the fractions where the denominator is 100, we can remove the denominator and put the % sign.For example, the fraction 23/100 can be written a
5 min read
Algebra
Variable in MathsA variable is like a placeholder or a box that can hold different values. In math, it's often represented by a letter, like x or y. The value of a variable can change depending on the situation. For example, if you have the equation y = 2x + 3, the value of y depends on the value of x. So, if you ch
5 min read
Polynomials| Degree | Types | Properties and ExamplesPolynomials are mathematical expressions made up of variables (often represented by letters like x, y, etc.), constants (like numbers), and exponents (which are non-negative integers). These expressions are combined using addition, subtraction, and multiplication operations.A polynomial can have one
9 min read
CoefficientA coefficient is a number that multiplies a variable in a mathematical expression. It tells you how much of that variable you have. For example, in the term 5x, the coefficient is 5 — it means 5 times the variable x.Coefficients can be positive, negative, or zero. Algebraic EquationA coefficient is
8 min read
Algebraic IdentitiesAlgebraic Identities are fundamental equations in algebra where the left-hand side of the equation is always equal to the right-hand side, regardless of the values of the variables involved. These identities play a crucial role in simplifying algebraic computations and are essential for solving vari
14 min read
Properties of Algebraic OperationsAlgebraic operations are mathematical processes that involve the manipulation of numbers, variables, and symbols to produce new results or expressions. The basic algebraic operations are:Addition ( + ): The process of combining two or more numbers to get a sum. For example, 3 + 5 = 8.Subtraction (−)
3 min read
Geometry
Lines and AnglesLines and Angles are the basic terms used in geometry. They provide a base for understanding all the concepts of geometry. We define a line as a 1-D figure that can be extended to infinity in opposite directions, whereas an angle is defined as the opening created by joining two or more lines. An ang
9 min read
Geometric Shapes in MathsGeometric shapes are mathematical figures that represent the forms of objects in the real world. These shapes have defined boundaries, angles, and surfaces, and are fundamental to understanding geometry. Geometric shapes can be categorized into two main types based on their dimensions:2D Shapes (Two
2 min read
Area and Perimeter of Shapes | Formula and ExamplesArea and Perimeter are the two fundamental properties related to 2-dimensional shapes. Defining the size of the shape and the length of its boundary. By learning about the areas of 2D shapes, we can easily determine the surface areas of 3D bodies and the perimeter helps us to calculate the length of
10 min read
Surface Areas and VolumesSurface Area and Volume are two fundamental properties of a three-dimensional (3D) shape that help us understand and measure the space they occupy and their outer surfaces.Knowing how to determine surface area and volumes can be incredibly practical and handy in cases where you want to calculate the
10 min read
Points, Lines and PlanesPoints, Lines, and Planes are basic terms used in Geometry that have a specific meaning and are used to define the basis of geometry. We define a point as a location in 3-D or 2-D space that is represented using coordinates. We define a line as a geometrical figure that is extended in both direction
14 min read
Coordinate Axes and Coordinate Planes in 3D spaceIn a plane, we know that we need two mutually perpendicular lines to locate the position of a point. These lines are called coordinate axes of the plane and the plane is usually called the Cartesian plane. But in real life, we do not have such a plane. In real life, we need some extra information su
6 min read
Trigonometry & Vector Algebra
Trigonometric RatiosThere are three sides of a triangle Hypotenuse, Adjacent, and Opposite. The ratios between these sides based on the angle between them is called Trigonometric Ratio. The six trigonometric ratios are: sine (sin), cosine (cos), tangent (tan), cotangent (cot), cosecant (cosec), and secant (sec).As give
4 min read
Trigonometric Equations | Definition, Examples & How to SolveTrigonometric equations are mathematical expressions that involve trigonometric functions (such as sine, cosine, tangent, etc.) and are set equal to a value. The goal is to find the values of the variable (usually an angle) that satisfy the equation.For example, a simple trigonometric equation might
9 min read
Trigonometric IdentitiesTrigonometric identities play an important role in simplifying expressions and solving equations involving trigonometric functions. These identities, which include relationships between angles and sides of triangles, are widely used in fields like geometry, engineering, and physics. Some important t
10 min read
Trigonometric FunctionsTrigonometric Functions, often simply called trig functions, are mathematical functions that relate the angles of a right triangle to the ratios of the lengths of its sides.Trigonometric functions are the basic functions used in trigonometry and they are used for solving various types of problems in
6 min read
Inverse Trigonometric Functions | Definition, Formula, Types and Examples Inverse trigonometric functions are the inverse functions of basic trigonometric functions. In mathematics, inverse trigonometric functions are also known as arcus functions or anti-trigonometric functions. The inverse trigonometric functions are the inverse functions of basic trigonometric function
11 min read
Inverse Trigonometric IdentitiesInverse trigonometric functions are also known as arcus functions or anti-trigonometric functions. These functions are the inverse functions of basic trigonometric functions, i.e., sine, cosine, tangent, cosecant, secant, and cotangent. It is used to find the angles with any trigonometric ratio. Inv
9 min read
Calculus
Introduction to Differential CalculusDifferential calculus is a branch of calculus that deals with the study of rates of change of functions and the behaviour of these functions in response to infinitesimal changes in their independent variables.Some of the prerequisites for Differential Calculus include:Independent and Dependent Varia
6 min read
Limits in CalculusIn mathematics, a limit is a fundamental concept that describes the behaviour of a function or sequence as its input approaches a particular value. Limits are used in calculus to define derivatives, continuity, and integrals, and they are defined as the approaching value of the function with the inp
12 min read
Continuity of FunctionsContinuity of functions is an important unit of Calculus as it forms the base and it helps us further to prove whether a function is differentiable or not. A continuous function is a function which when drawn on a paper does not have a break. The continuity can also be proved using the concept of li
13 min read
DifferentiationDifferentiation in mathematics refers to the process of finding the derivative of a function, which involves determining the rate of change of a function with respect to its variables.In simple terms, it is a way of finding how things change. Imagine you're driving a car and looking at how your spee
2 min read
Differentiability of a Function | Class 12 MathsContinuity or continuous which means, "a function is continuous at its domain if its graph is a curve without breaks or jumps". A function is continuous at a point in its domain if its graph does not have breaks or jumps in the immediate neighborhood of the point. Continuity at a Point: A function f
11 min read
IntegrationIntegration, in simple terms, is a way to add up small pieces to find the total of something, especially when those pieces are changing or not uniform.Imagine you have a car driving along a road, and its speed changes over time. At some moments, it's going faster; at other moments, it's slower. If y
3 min read
Probability and Statistics
Basic Concepts of ProbabilityProbability is defined as the likelihood of the occurrence of any event. It is expressed as a number between 0 and 1, where 0 is the probability of an impossible event and 1 is the probability of a sure event.Concepts of Probability are used in various real life scenarios : Stock Market : Investors
7 min read
Bayes' TheoremBayes' Theorem is a mathematical formula used to determine the conditional probability of an event based on prior knowledge and new evidence. It adjusts probabilities when new information comes in and helps make better decisions in uncertain situations.Bayes' Theorem helps us update probabilities ba
13 min read
Probability Distribution - Function, Formula, TableA probability distribution is a mathematical function or rule that describes how the probabilities of different outcomes are assigned to the possible values of a random variable. It provides a way of modeling the likelihood of each outcome in a random experiment.While a Frequency Distribution shows
13 min read
Descriptive StatisticStatistics is the foundation of data science. Descriptive statistics are simple tools that help us understand and summarize data. They show the basic features of a dataset, like the average, highest and lowest values and how spread out the numbers are. It's the first step in making sense of informat
5 min read
What is Inferential Statistics?Inferential statistics is an important tool that allows us to make predictions and conclusions about a population based on sample data. Unlike descriptive statistics, which only summarize data, inferential statistics let us test hypotheses, make estimates, and measure the uncertainty about our predi
7 min read
Measures of Central Tendency in StatisticsCentral tendencies in statistics are numerical values that represent the middle or typical value of a dataset. Also known as averages, they provide a summary of the entire data, making it easier to understand the overall pattern or behavior. These values are useful because they capture the essence o
11 min read
Set TheorySet theory is a branch of mathematics that deals with collections of objects, called sets. A set is simply a collection of distinct elements, such as numbers, letters, or even everyday objects, that share a common property or rule.Example of SetsSome examples of sets include:A set of fruits: {apple,
3 min read
Practice