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Sin x Graph Explained with Key Properties

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How to Draw the Sin x Graph Step by Step with Formula and Period

When we write trigonometric ratios, they can also be represented in a graphical format where the functions of the variable are the measure of the angle. These angles can be either in the degree or radians. 

Let’s talk about the Sinx graph. The graph of sin function is represented by the equation: y=Sin(x). 

The graphical representation of this graph is:


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Properties Of The y = Sinx Graph Or The Sine Function

Now that we know how the graph of sin looks, let’s have a look at its properties. These values of the sine function will help you while solving problems relating to the Sinx graph.

  • Domain - It is the set of all values that can be used as input for which the function is defined. All values that can be used as input for the function are in the domain of the function. The domain of the sine function is from (-∞,∞) .

  • Range - It is defined as the set of all values that are outputs of the function for all the values in the domain of the function. The range of the y Sinx Graph is [-1,1]. It can also be represented as -1y1.\[-1\leq{y}\leq1\]

  • Y-Intercept- It represents the coordinates of the point where the sin x graph intersects with the y-axis. The y-intercept of the y sinx graph is (0,0) which means that the graph passes through the Y-axis at the origin. Therefore, when the value of x=0, the value of Y is also 0.

  • X-Intercept - It is defined as the coordinates of the points where the Sin x graph intercepts the X-axis. The x-intercept of the Sinx graph is nπ, where n is an integer. It means that the graph cuts the x-axis at equal intervals of π. Here, n is an integer and therefore can also take negative values. 

  • Period: The period of the y sinx graph is 2π. This means that after an interval of 2π, the graph repeats itself. 

  • Continuity- The graph of Sine is continuous on (-∞,∞) which states the function is continuous everywhere. 

  • Symmetry- The y = Sinx Graph is symmetrical at the origin which means that it is an odd function.  If a graph is symmetrical at the Y-axis it is termed as an even function. Even function is represented by f(x)=f(-x) and odd function is represented by f(x)=-f(x).


Drawing A Sine Function

The y Sin x graph is representative of a periodic function y = Sin(x) with a period of 2π. The graph is continuous on (-∞,∞) so we will draw the graph in the interval [0,2π]. Follow these steps to draw the graph of the sine function.

  1. Draw a Y-axis with numbering 0,1,2.. etc.

  2. Draw an X-axis with notations π/2, π, 3π/2, 2π.. Etc.

  3. The sinx curve intersects the X-axis at 0, π, 2π, 3π… and so on.

  4. The sinx curve intersects the Y-axis only at the origin. 

  5. Let’s find the values of y for values of x

  • At x=0, y=Sin(0)=0

  • At x=π/2, y=Sin(π/2)=1

  • At x=π, y=Sin(π)=0

  1. Draw the sinx curve by joining the points (0,0), (π/2,1) and (2π,0). It will look something like this:


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Other curves that follow this shape are termed “sinusoidal” after the sine function. This is also referred to as the sine curve and is commonly found in radio and electronic circuits. 


Graph of Mod Sinx  

The graph of mod sinx is given below:

y=|Sin(x)|


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The range of this function now changes from (-1,1) to (0,1), because the output values need to be positive as per the definition of the mode function.

One another way graph of mod sinx can be represented is if the function becomes:

y=Sin|x|

Here, the domain of the function changes from (-∞,∞)to (0,∞).

Its graph can be represented as :


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Graph of xSinx 

Graph of xsinx can be obtained by:

First, we will draw the graph of y=Sin x

Let’s obtain the values of y for values of x.

f(0)=0

f(π/2)=π/2

f(π)=0

f(3π/2)=-3π/2

f(2π)=0

f(5π/2)=5π/2

And so on.

The points which lie on y=x are:

(π/2,π/2), (5π/2, 5π/2), … 

The points which lie on y=-x are:

(3π/2, 3π/2), (7π/2, 7π/2),...

Also, 

f(x)=f(-x), therefore the function is an even function. 

An even function is one where the graph is symmetrical about the Y-axis. 

The graph then comes out to be this.


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(Image will be Uploaded soon)

FAQs on Sin x Graph Explained with Key Properties

1. What is the sine graph?

The sine graph is the graph of the function y = sin x, which represents a smooth, periodic wave that oscillates between −1 and 1. It is also called a sinusoidal curve.

  • The graph repeats every 2π radians (or 360°).
  • The maximum value is 1 and the minimum value is −1.
  • It passes through the origin (0, 0).
  • It is widely used in trigonometry, physics, and engineering.

2. What is the period of the sin x graph?

The period of y = sin x is 2π radians (or 360°). The period is the length of one complete cycle of the wave.

  • One full cycle occurs from 0 to .
  • For y = sin(bx), the period becomes 2π / |b|.
  • If b = 2, the period is π.
This shows how horizontal stretching or compression affects the sine graph.

3. What is the amplitude of the sine graph?

The amplitude of y = sin x is 1. Amplitude is the distance from the midline to the maximum or minimum value.

  • For y = a sin x, amplitude = |a|.
  • If a = 3, the amplitude is 3.
  • If a = −2, the amplitude is 2 (the negative only reflects the graph).
Amplitude controls the vertical stretch of the sine curve.

4. What are the key points of the sin x graph?

The key points of y = sin x in one cycle help sketch the graph accurately. The five main points between 0 and 2π are:

  • (0, 0)
  • (π/2, 1)
  • (π, 0)
  • (3π/2, −1)
  • (, 0)
These points form one complete sine wave.

5. How do you sketch the sin x graph step by step?

To sketch y = sin x, plot the key points of one full period and draw a smooth curve through them.

  • Step 1: Mark the x-axis from 0 to .
  • Step 2: Plot (0, 0).
  • Step 3: Plot (π/2, 1).
  • Step 4: Plot (π, 0).
  • Step 5: Plot (3π/2, −1).
  • Step 6: Plot (, 0).
  • Step 7: Draw a smooth wave through the points.
Repeat the pattern for additional cycles.

6. What is the domain and range of sin x?

The domain of sin x is all real numbers, and its range is −1 to 1. This means:

  • Domain: (−∞, ∞)
  • Range: [−1, 1]
The sine function is defined for every real value of x and never exceeds 1 or goes below −1.

7. How does y = a sin bx change the sine graph?

The function y = a sin bx changes the amplitude and period of the sine graph. Specifically:

  • Amplitude = |a|
  • Period = 2π / |b|
For example, in y = 2 sin(3x):
  • Amplitude = 2
  • Period = 2π/3
This transformation stretches or compresses the graph vertically and horizontally.

8. What is the phase shift in a sine graph?

The phase shift is the horizontal movement of a sine graph from its standard position. In the function y = a sin(bx − c), the phase shift is c/b units to the right.

  • If c/b is positive, shift right.
  • If c/b is negative, shift left.
  • Example: y = sin(x − π/4) shifts right by π/4.
Phase shift changes where the cycle begins.

9. What is the difference between sin x and cos x graphs?

The main difference between sin x and cos x graphs is their starting point.

  • y = sin x starts at (0, 0).
  • y = cos x starts at (0, 1).
  • Both have amplitude 1 and period .
The cosine graph is essentially the sine graph shifted left by π/2.

10. Where is the sine graph used in real life?

The sine graph is used to model periodic and oscillating phenomena in real life. Common applications include:

  • Sound waves and vibrations
  • Light waves in physics
  • Alternating current (AC) electricity
  • Tides and seasonal patterns
Because it represents smooth, repeating motion, the sine curve is fundamental in science and engineering.