28 Facts About Laplace transform

1.

In mathematics, the Laplace transform, named after its discoverer Pierre-Simon Laplace, is an integral transform that converts a function of a real variable to a function of a complex variable.

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2.

The transform has many applications in science and engineering because it is a tool for solving differential equations.

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3.

Laplace transform is named after mathematician and astronomer Pierre-Simon, marquis de Laplace, who used a similar transform in his work on probability theory.

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4.

Current widespread use of the Laplace transform came about during and soon after World War II, replacing the earlier Heaviside operational calculus.

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5.

The advantages of the Laplace transform had been emphasized by Gustav Doetsch, to whom the name Laplace transform is apparently due.

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6.

However, in 1785, Laplace took the critical step forward when, rather than simply looking for a solution in the form of an integral, he started to apply the transforms in the sense that was later to become popular.

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7.

Laplace transform then went on to apply the Laplace transform in the same way and started to derive some of its properties, beginning to appreciate its potential power.

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8.

Laplace transform recognised that Joseph Fourier's method of Fourier series for solving the diffusion equation could only apply to a limited region of space, because those solutions were periodic.

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9.

In 1809, Laplace applied his transform to find solutions that diffused indefinitely in space.

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10.

Laplace transform of a function, defined for all real numbers, is the function, which is a unilateral transform defined by.

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11.

The Laplace transform is defined and injective for suitable spaces of tempered distributions.

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12.

The inverse Laplace transform is given by the following complex integral, which is known by various names :.

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13.

In practice, it is typically more convenient to decompose a Laplace transform into known transforms of functions obtained from a table, and construct the inverse by inspection.

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14.

The Laplace transform has applications throughout probability theory, including first passage times of stochastic processes such as Markov chains, and renewal theory.

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15.

The Laplace transform is usually understood as conditionally convergent, meaning that it converges in the former but not in the latter sense.

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16.

The Laplace transform is analytic in the region of absolute convergence: this is a consequence of Fubini's theorem and Morera's theorem.

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17.

Laplace transform has a number of properties that make it useful for analyzing linear dynamical systems.

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18.

The Laplace transform turns integral equations and differential equations to polynomial equations, which are much easier to solve.

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19.

Laplace transform can be viewed as a continuous analogue of a power series.

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20.

In other words, the Laplace transform is a continuous analog of a power series, in which the discrete parameter is replaced by the continuous parameter, and is replaced by.

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21.

The Laplace transform is usually restricted to transformation of functions of with.

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22.

The generalized Borel Laplace transform allows a different weighting function to be used, rather than the exponential function, to Laplace transform functions not of exponential type.

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23.

Since an ordinary Laplace transform can be written as a special case of a two-sided transform, and since the two-sided transform can be written as the sum of two one-sided transforms, the theory of the Laplace-, Fourier-, Mellin-, and Z-transforms are at bottom the same subject.

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24.

Unilateral Laplace transform takes as input a function whose time domain is the non-negative reals, which is why all of the time domain functions in the table below are multiples of the Heaviside step function,.

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25.

Laplace transform is often used in circuit analysis, and simple conversions to the -domain of circuit elements can be made.

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26.

Laplace transform is used frequently in engineering and physics; the output of a linear time-invariant system can be calculated by convolving its unit impulse response with the input signal.

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27.

Laplace transform can be used to solve differential equations and is used extensively in mechanical engineering and electrical engineering.

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28.

The Laplace transform reduces a linear differential equation to an algebraic equation, which can then be solved by the formal rules of algebra.

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