The time interval between two waves is known as a Period whereas a duty that repeats its worths at consistent intervals or periods is well-known as a Periodic Function. In other words, a routine function is a role that repeats its worths after eincredibly specific interval.

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The duration of the attribute is this particular interval stated above.

A attribute f will certainly be periodic with duration m, so if we have

f (a + m) = f (a), For eextremely m > 0.

It shows that the function f(a) possesses the same worths after an interval of “m”. One deserve to say that after eexceptionally interval of “m” the attribute f repeats all its worths.

For instance – The sine feature i.e. sin a has a duration 2 π because 2 π is the smallest number for which sin (a + 2π) = sin a, for all a.

We may additionally calculate the period utilizing the formula acquired from the standard sine and also cosine equations. The duration for attribute y = A sin(Bx + C) and also y = A cos(Bx + C) is 2π/|B| radians.

The reciprocal of the period of a duty = frequency

Frequency is characterized as the number of cycles completed in one second. If the duration of a function is delisted by P and also f be its frequency, then –f =1/ P.

Fundapsychological Period of a Function

The fundamental duration of a duty is the duration of the attribute which are of the develop,


f(x+k)=f(x), then k is dubbed the period of the function and the attribute f is referred to as a regular feature.

Now, let us define the function h(t) on the interval <0, 2> as follows:


If we extfinish the function h to every one of R by the equation,


=> h is periodic via period 2.

The graph of the feature is shown listed below.


How to Find the Period of a Function?

If a role repeats over at a continuous period we say that is a routine attribute.It is stood for like f(x) = f(x + p), p is the actual number and also this is the duration of the feature.Period means the time interval between the two cases of the wave.

Period of a Trigonometric Function

The distance between the repetition of any feature is called the period of the function. For a trigonometric feature, the size of one finish cycle is dubbed a period. For any kind of trigonomeattempt graph function, we deserve to take x = 0 as the starting point.

In general, we have 3 standard trigonometric functions like sin, cos and tan functions, having -2π, 2π and π period respectively.

Sine and also cosine attributes have actually the creates of a periodic wave:


Period: It is represented as “T”. A duration is a distance among 2 repeating points on the graph attribute.Amplitude: It is represented as “A”. It is the distance between the middle suggest to the greatest or lowest allude on the graph function.

sin(aθ) = 2πa and cos(aθ) = 2πa

Period of a Sine Function

If we have a function f(x) = sin (xs), wright here s > 0, then the graph of the feature makes complete cycles between 0 and also 2π and each of the function have actually the duration, p = 2π/s

Now, let’s talk about some examples based on sin function:

Let us discuss the graph of y = sin 2x


Period = πAxis: y = 0 Amplitude: 1Maximum worth = 1
Minimum worth = -1Domain: x : x ∈ R Range = < -1, 1>

Period of a Tangent Function

If we have a role f(a) = tan (as), where s > 0, then the graph of the function makes complete cycles between −π/2, 0 and π/2 and also each of the function have actually the period of p = π/s


Periodic Functions Examples

Let’s learn some of the examples of periodic features.

Example 1:

Find the duration of the offered periodic function f(x) = 9 sin(6x + 5).


Given periodic attribute is f(x) = 9 sin(6x+ 5)

Coefficient of x = B = 6

Period = 2π/ |B|, here period of the periodic feature = 2π/ 6 = π/3

Example 2:

What is the period of the following regular function?

f(a) = 6 cos 5a


The given periodic function is f(a) = 6 cos 5a. We have actually the formula for the duration of the attribute.

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Period = 2π/B,

From the provided, B = 5

Hence, the duration of the given periodic function = 2π/5

Example 3:

Graph of y = 4 sin(a/2)



Period = 4πAxis: y = 0 Amplitude: 4Maximum worth = 4Minimum worth = -4Domain: x : x ∈ R Range = < -4, 4>

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