Laplace transform Calculator

How to use the Laplace transform Calculator?

Here are step-by-step instructions on how to use the Laplace Transform Calculator:

Step-1: Enter the Function:

In the input box labeled “Enter the function f(t):”, type in the function f(t) for which you want to find the Laplace transform. 

Step-2: Click “Calculate Laplace Transform”:

After entering the function, click on the “Calculate Laplace Transform” button.


How to find the Laplace transform?

To find the Laplace transform of a function, we can use the definition of the Laplace transform, which is:

F\left(s\right)=\int _0^{\infty }e^{-st}f\left(t\right)dt

where F(s) is the Laplace transform of the function f(t), and s is a complex variable.


Example on the Laplace transform.

 
Find the Laplace transform of the function f(t)=t

Use the definition of the Laplace transform to find the Laplace transform of f(t)=t

F\left(s\right)=\int _0^{\infty }e^{-st}tdt

Use the integration by parts method.

Substitute

u=t\:\:\:\:\:\:\:and\:\:\:\:\:\:\:\:\:v'=e^{-st}\\

u'=\frac{d}{dt}\left(t\right)\:\:\:\:\:\:\:and\:\:\:\:\:\:\:\:\:v=\int e^{-st}\\

u'=1\:\:\:\:\:\:\:and\:\:\:\:\:\:\:\:\:v=-\frac{1}{s}e^{-st}\\

The rule for integration by parts is given by, \int uv'=uv-\int u'v

F\left(s\right)=\left[t\left(-\frac{1}{s}e^{-st}\right)-\int 1\left(-\frac{1}{s}e^{-st}\right)\right]_0^{\infty }\\

F\left(s\right)=\left[-\frac{te^{-st}}{s}-\int 1\left(-\frac{e^{-st}}{s}\right)\right]_0^{\infty }\\

F\left(s\right)=\left[-\frac{te^{-st}}{s}+\int \frac{e^{-st}}{s}\right]_0^{\infty }\\

F\left(s\right)=\left[-\frac{te^{-st}}{s}+\frac{1}{s}\int e^{-st}\right]_0^{\infty }\\

F\left(s\right)=\left[-\frac{te^{-st}}{s}+\frac{1}{s}\left(-\frac{1}{s}e^{-st}\right)\right]_0^{\infty }\\

F\left(s\right)=\left[-\frac{te^{-st}}{s}-\frac{1}{s^2}e^{-st}\right]_0^{\infty }\\

F\left(s\right)=-\frac{\infty e^{-s\cdot \infty }}{s}-\frac{1}{s^2}e^{-s\cdot \infty }-\left(-\frac{0e^{-s\cdot 0}}{s}-\frac{1}{s^2}e^{-s\cdot 0}\right)\\

F\left(s\right)=-\frac{0}{s}-\frac{1}{s^2}\cdot 0-\left(-\frac{0}{s}-\frac{1}{s^2}\cdot 1\right)\\

F\left(s\right)=0+0-\left(0-\frac{1}{s^2}\right)\\

F\left(s\right)=-\left(-\frac{1}{s^2}\right)\\

F\left(s\right)=\frac{1}{s^2}\\


FAQs on the Laplace transform:

1) Who invented the Laplace transform?

Answer: The concept of the Laplace transform is named after Pierre-Simon Laplace, a French mathematician and astronomer who lived from 1749 to 1827

2) What is the Laplace Transform?

Answer: The Laplace transform is an integral transform used to convert a function of time f(t) into a function of a complex variable s. It is widely used in engineering and mathematics for solving differential equations, analyzing systems, and solving initial value problems.

3) Why is the Laplace Transform Useful?

Answer: The Laplace transform is useful because it simplifies the process of solving differential equations. It transforms differential equations into algebraic equations, which are often easier to solve. Additionally, it provides a convenient way to analyze systems in the frequency domain.
How is the Laplace Transform denoted?

4) How is the Laplace Transform denoted?

Answer: The Laplace transform of a function f(t) is denoted by F(s), where s is a complex variable. Mathematically, it is represented as: F\left(s\right)=\int _0^{\infty }e^{-st}f\left(t\right)dt

5) What is the Laplace of 1?

Answer: The Laplace transform of the constant function 1 is: L\left\{1\right\}=\frac{1}{s}


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