🕷️ Crawler Inspector

URL Lookup

Direct Parameter Lookup

Raw Queries and Responses

1. Shard Calculation

Query:
Response:
Calculated Shard: 180 (from laksa154)

2. Crawled Status Check

Query:
Response:

3. Robots.txt Check

Query:
Response:

4. Spam/Ban Check

Query:
Response:

5. Seen Status Check

ℹ️ Skipped - page is already crawled

đź“„
INDEXABLE
âś…
CRAWLED
3 days ago
🤖
ROBOTS ALLOWED

Page Info Filters

FilterStatusConditionDetails
HTTP statusPASSdownload_http_code = 200HTTP 200
Age cutoffPASSdownload_stamp > now() - 6 MONTH0.1 months ago
History dropPASSisNull(history_drop_reason)No drop reason
Spam/banPASSfh_dont_index != 1 AND ml_spam_score = 0ml_spam_score=0
CanonicalPASSmeta_canonical IS NULL OR = '' OR = src_unparsedNot set

Page Details

PropertyValue
URLhttps://calcworkshop.com/laplace-transform/laplace-transform-overview/
Last Crawled2026-04-19 20:10:49 (3 days ago)
First Indexed2018-10-17 13:12:52 (7 years ago)
HTTP Status Code200
Content
Meta TitleLaplace Transform Techniques (Simplifying Differential Equations)
Meta DescriptionDiscover the power of the Laplace Transform to simplify complex differential equations, with examples, tips, and a handy transforms table.
Meta Canonicalnull
Boilerpipe Text
Ever wondered how to simplify “difficult” ordinary differential equations ? The Laplace Transform is like a skilled translator, converting these complex equations into more approachable forms. Jenn, Founder Calcworkshop ® , 15+ Years Experience (Licensed & Certified Teacher) Used extensively in engineering , the Laplace Transform takes a function of a positive real variable (x or t), often represented as “ time ,” and transforms it into a function of a complex variable, commonly called “ frequency .” Let’s jump in and see what the Laplace transform is all about! Understanding Improper Integrals Okay, so to better understand the Laplace transform, we must first understand the improper integral. If \(f(x)\) is a continuous function, then the improper integral \(\int_{0}^{\infty} f(x) d x\) exists if the integral approaches a finite limit. In other words, if \(\int_{0}^{\infty} f(x) d x=L\), where \(\mathrm{L}\) is a finite limit, then \(\int_{0}^{\infty} f(x) d x\) converges to the value of L. And if the limit does not exist, then the improper integral diverges. Convergence of Improper Integrals Now it’s time to look at an important improper integral because it builds the foundation for what we are about to see…. If the improper integral \(\int_{0}^{\infty} e^{-s x} f(x) d x\) converges for a value of \(s=s_{0}\), then it converges for every \(s>s_{0}\). And this integral, if it exists, is a function of \(\mathrm{s}\) and is called the Laplace Transform! Definition of the Laplace Transform By definition, the Laplace transform assumes that \(f(x)\) is a function for which the integral exists for some value of \(s\), then we say it is denoted as: \begin{align*} L\{f(x)\}=F(s)=\int_{0}^{\infty} e^{-s x} f(x) d x \end{align*} Basic Transforms Table Now, computing transforms directly can be a bit complicated and tedious, so it’s by far easier to use a table of transforms to help simplify the process for us. \begin{equation} \begin{array}{|c|c|} \hline \text { If } f(x)= & \text { Then } L\{f(x)\}=F(s)= \\ \hline 1 & \frac{1}{s} \\ \hline k & \frac{k}{s}>0 \\ \hline e^{a x} & \frac{1}{s-a} \\ \hline x^n, n=1,2,3, \ldots & \frac{n !}{s^{n+1}} \\ \hline x^n e^{a x}, n=1,2,3, \ldots & \frac{n !}{(s-a)^{n+1}} s>a \\ \hline \sin (a x) & \frac{a}{s^2+a^2} \\ \hline \cos (a x) & \frac{s}{s^2+a^2} \\ \hline \sinh (a x) & \frac{a}{s^2-a^2}, s>|a| \\ \hline \cosh (a x) & \frac{s}{s^2-a^2}, s>|a| \\ \hline x \sin (a x) & \frac{2 a s}{\left(s^2+a^2\right)^2} \\ \hline x \cos (a x) & \frac{s^2-a^2}{\left(s^2+a^2\right)^2} \\ \hline e^{a x} \sin (b x) & \frac{b}{(s-a)^2+b^2} \\ \hline e^{a x} \cos (b x) & \frac{s-a}{(s-a)^2+b^2} \\ \hline \end{array} \end{equation} Keep in mind that this table isn’t exhaustive, but it does provide a solid foundation for harnessing this impressive new tool! You might be wondering, “What is this, and how does it help solve differential equations?” Great question! Let’s explore a few examples together to better understand its applications. Properties of the Laplace Transform But before we do, I want to point out two critical properties , as the Laplace transform is linear and upholds both homogeneity and superposition . The Laplace Transform has two essential properties, linearity and superposition , which make it useful for solving complex problems: Linearity (Homogeneity) : This means that if you multiply a function by a constant, you can just multiply the Laplace Transform of that function by the same constant. Superposition : This means that if you add two functions together, you can simply add their Laplace Transforms separately. These properties make working with the Laplace Transform easier and more efficient , helping us analyze complex systems and solve differential equations in various fields like engineering, physics, and mathematics. If \(\mathrm{a}\) is a constant and \(\mathrm{f}\) and \(\mathrm{g}\) are functions, then \begin{equation} \begin{aligned} & L\{a f(x)\}=a L\{f(x)\} \\ & L\{f(x) \pm g(x)\}=L\{f(x)\} \pm L\{g(x)\} \end{aligned} \end{equation} Example: Laplace Transform of a Polynomial Function Find the Laplace transform of the function \(f(x)=3 x^{5}\) First, we will use our first property of linearity and pull out the leading coefficient. \begin{equation} \begin{aligned} & L\left\{3 x^5\right\} \\ & 3 L\left\{x^5\right\} \end{aligned} \end{equation} Next, we will notice that our function is a polynomial of the form \(x^{n}\) therefore, we can apply its transform as follows. \begin{equation} \begin{aligned} & L\left\{x^n\right\}=\frac{n !}{s^{n+1}} \\ & 3 L\left\{x^5\right\}=3\left(\frac{5 !}{s^{5+1}}\right)=3\left(\frac{5 !}{s^6}\right)=\frac{3(120)}{s^6}=\frac{360}{s^6}, s>0 \end{aligned} \end{equation} Easy, right? Example: Laplace Transform w/ Exponential and Trig Functions Find the Laplace transform of the function \(f(x)=e^{3 x}+\cos (5 x)\) First, we will use our second property and separate our two terms. \begin{equation} \begin{aligned} & L\left\{e^{3 x}+\cos (5 x)\right\} \\ & L\left\{e^{3 x}\right\}+L\{\cos (5 x)\} \end{aligned} \end{equation} Next, we will use our table to find our transformation for the exponential function and the trigonometric function separately, as follows. \begin{align*} \begin{aligned} & L\left\{e^{a x}\right\}=\frac{1}{s-a} \text { and } L\{\cos (a x)\}=\frac{s}{s^{2}+a^{2}} \\ & L\left\{e^{3 x}\right\}+L\{\cos (5 x)\}=\frac{1}{s-3}+\frac{s}{s^{2}+5^{2}} \\ & L\left\{e^{3 x}\right\}+L\{\cos (5 x)\}=\frac{1}{s-3}+\frac{s}{s^{2}+25}, s>3 \end{aligned} \end{align*} Nothing to it! Let’s Wrap Up Together, you’ll explore the Laplace Transform by: Understanding linearity and breaking up each term into separate parts. Discussing sufficient conditions of existence, such as piecewise continuous functions. Working through five detailed examples using the Definition of the Laplace Transform, Improper Integrals, and Integration by Parts. Creating a table of Basic Transforms and applying them to seven more examples. Let’s go! Video Tutorial w/ Full Lesson & Detailed Examples Get access to all the courses and over 450 HD videos with your subscription Monthly and Yearly Plans Available Get My Subscription Now Still wondering if CalcWorkshop is right for you? Take a Tour and find out how a membership can take the struggle out of learning math.
Markdown
[Calcworkshop](https://calcworkshop.com/) [Login](https://calcworkshop.com/login/) - [Home](https://calcworkshop.com/) - [Reviews](https://calcworkshop.com/reviews/) - [Courses](https://calcworkshop.com/courses/) - [Algebra I & II](https://calcworkshop.com/algebra/) - [Intro Algebra](https://calcworkshop.com/intro-algebra/) - [Solving Equations](https://calcworkshop.com/solving-equations/) - [Exponents](https://calcworkshop.com/exponents/) - [Polynomials](https://calcworkshop.com/polynomials/) - [Factoring](https://calcworkshop.com/factoring/) - [Rationals](https://calcworkshop.com/rationals/) - [Graphing Linear Equations](https://calcworkshop.com/graphing-linear-equations/) - [Systems of Equations](https://calcworkshop.com/systems-equations/) - [Radicals](https://calcworkshop.com/radicals/) - [Functions & Statistics](https://calcworkshop.com/functions-statistics/) - [Geometry](https://calcworkshop.com/high-school-geometry/) - [Basic Geometry](https://calcworkshop.com/basic-geometry/) - [Reasoning & Proofs](https://calcworkshop.com/reasoning-proof/) - [Congruent Triangles](https://calcworkshop.com/congruent-triangles/) - [Quadrilaterals](https://calcworkshop.com/quadrilaterals/) - [Similarity](https://calcworkshop.com/similarity/) - [Triangles & Trig](https://calcworkshop.com/triangle-trig/) - [Circles](https://calcworkshop.com/circle/) - [Polygons & Circles](https://calcworkshop.com/polygons-circles/) - [Volume & Surface Area](https://calcworkshop.com/volume-surface-area/) - [Transformations](https://calcworkshop.com/transformations/) - [Pre-Calculus](https://calcworkshop.com/precalculus/) - [Trigonometry](https://calcworkshop.com/trigonometry/) - [Trigonometric Functions](https://calcworkshop.com/trigonometric-functions/) - [Radian Measure](https://calcworkshop.com/radian-measure/) - [Graphing Trig Functions](https://calcworkshop.com/graphing-trig-functions/) - [Trig Identities](https://calcworkshop.com/trig-identities/) - [Trig Equations](https://calcworkshop.com/trig-equations/) - [Law of Sines and Cosines](https://calcworkshop.com/law-sines-cosines/) - [Vector Applications](https://calcworkshop.com/vector-applications/) - [Polar Equations](https://calcworkshop.com/polar-equations/) - [Complex Numbers](https://calcworkshop.com/complex-numbers/) - [Math Analysis](https://calcworkshop.com/math-analysis/) - [Intro to Math Analysis](https://calcworkshop.com/intro-math-analysis/) - [Functions and Graphs](https://calcworkshop.com/functions-graphs/) - [Expos and Logs](https://calcworkshop.com/expos-logs/) - [Polynomial Functions](https://calcworkshop.com/polynomial-function/) - [Rational Functions](https://calcworkshop.com/rational-functions/) - [Conic Sections](https://calcworkshop.com/conic-sections/) - [Series & Sequences](https://calcworkshop.com/series-sequences/) - [Calculus 1, 2, & 3]() - [Business Calculus](https://calcworkshop.com/business-calculus/) - [Calculus 1](https://calcworkshop.com/calculus-1/) - [PreCalc Review](https://calcworkshop.com/pre-calculus-review/) - [Limits](https://calcworkshop.com/limits/) - [Derivatives](https://calcworkshop.com/derivatives/) - [Application of Derivatives](https://calcworkshop.com/application-derivatives/) - [Integrals](https://calcworkshop.com/integrals/) - [Final Exam](https://calcworkshop.com/calculus-1-final-exam/) - [Calculus 2](https://calcworkshop.com/calculus-2/) - [Integrals](https://calcworkshop.com/integrals/) - [Applications of Integrals](https://calcworkshop.com/applications-integrals/) - [Diff-EQs](https://calcworkshop.com/diff-eqs/) - [Polar Functions](https://calcworkshop.com/polar-functions/) - [Parametric and Vector Functions](https://calcworkshop.com/parametric-vector-functions/) - [Sequences and Series](https://calcworkshop.com/sequences-series/) - [Final Exam](https://calcworkshop.com/calculus-2-final-exam/) - [Calculus 3](https://calcworkshop.com/calculus-3/) - [Vectors and The Geometry of Space](https://calcworkshop.com/vectors-and-the-geometry-of-space/) - [Vector Functions](https://calcworkshop.com/vector-functions/) - [Partial Derivatives](https://calcworkshop.com/partial-derivatives/) - [Multiple Integrals](https://calcworkshop.com/multiple-integrals/) - [Vector Calculus](https://calcworkshop.com/vector-calculus/) - [Final Exam](https://calcworkshop.com/calculus-3-final-exam/) - [Statistics & Prob](https://calcworkshop.com/probability-and-statistics/) - [Exploring Data](https://calcworkshop.com/exploring-data/) - [Probability](https://calcworkshop.com/probability/) - [Discrete Distribution](https://calcworkshop.com/discrete-probability-distribution/) - [Continuous Distribution](https://calcworkshop.com/continuous-probability-distribution/) - [Joint Distribution](https://calcworkshop.com/joint-probability-distribution/) - [Confidence Interval](https://calcworkshop.com/confidence-interval/) - [Hypothesis Testing](https://calcworkshop.com/hypothesis-test/) - [Linear Regression](https://calcworkshop.com/linear-regression/) - [Discrete Math](https://calcworkshop.com/discrete-math/) - [Logic](https://calcworkshop.com/logic/) - [Proofs](https://calcworkshop.com/proofs/) - [Sets](https://calcworkshop.com/set-theory/) - [Number Theory](https://calcworkshop.com/number-theory/) - [Functions](https://calcworkshop.com/functions/) - [Combinatorics](https://calcworkshop.com/combinatorics/) - [Relations](https://calcworkshop.com/relations/) - [Trees & Graphs](https://calcworkshop.com/trees-graphs/) - [Linear Algebra](https://calcworkshop.com/linear-algebra/) - [Linear Equations](https://calcworkshop.com/linear-equations/) - [Matrix Algebra](https://calcworkshop.com/matrix-algebra/) - [Determinants](https://calcworkshop.com/determinates/) - [Vector Spaces](https://calcworkshop.com/vector-spaces/) - [Eigenvalues and Eigenvectors](https://calcworkshop.com/eigenvalues/) - [Orthogonality and Least Squares](https://calcworkshop.com/orthogonality/) - [Symmetric Matrices](https://calcworkshop.com/symmetric-matrices/) - [Final Exam](https://calcworkshop.com/linear-algebra-final-exam/) - [Diff-EQs](https://calcworkshop.com/differential-equations/) - [Intro to DiffEqs](https://calcworkshop.com/intro-to-diffeqs/) - [First Order Differential Equations](https://calcworkshop.com/first-order-differential-equations/) - [Second Order Differential Equations](https://calcworkshop.com/second-order-differential-equations/) - [Series Solutions](https://calcworkshop.com/series-solutions-diff-eqs/) - [Laplace Transform](https://calcworkshop.com/laplace-transform/) - [Systems of Differential Equations](https://calcworkshop.com/systems-of-differential-equations/) - [Final Exam](https://calcworkshop.com/differential-equations-final-exam/) - [Praxis](https://calcworkshop.com/praxis-math/) - [FAQs](https://calcworkshop.com/faq/) - [About](https://calcworkshop.com/about-me/) - [Contact](https://calcworkshop.com/contact/) - [Login](https://calcworkshop.com/login/) [Home](https://calcworkshop.com/) » [Laplace Transform](https://calcworkshop.com/laplace-transform/) » **Laplace Transform** # **Laplace Transform Techniques** Simplifying Differential Equations // Last Updated: April 18, 2023 - [Watch Video](https://calcworkshop.com/laplace-transform/laplace-transform-overview/#chapter) // Ever wondered how to **simplify “difficult” ordinary differential equations**? The *Laplace Transform* is like a skilled translator, converting these complex equations into more approachable forms. ![Jenn (B.S., M.Ed.) of Calcworkshop® teaching laplace transforms](https://calcworkshop.com/wp-content/uploads/jenn-calcworkshop-laplace-transforms.jpg) Jenn, Founder Calcworkshop®, 15+ Years Experience (Licensed & Certified Teacher) Used extensively in **engineering**, the Laplace Transform takes a function of a positive real variable (x or t), often represented as “*time*,” and transforms it into a function of a complex variable, commonly called “*frequency*.” Let’s **jump in** and see what the Laplace transform is all about\! ## Understanding Improper Integrals Okay, so to better understand the Laplace transform, we must first understand the improper integral. If \\(f(x)\\) is a continuous function, then the improper integral \\(\\int\_{0}^{\\infty} f(x) d x\\) exists if the integral approaches a finite limit. In other words, if \\(\\int\_{0}^{\\infty} f(x) d x=L\\), where \\(\\mathrm{L}\\) is a finite limit, then \\(\\int\_{0}^{\\infty} f(x) d x\\) converges to the value of L. And if the limit does not exist, then the improper integral diverges. ### Convergence of Improper Integrals Now it’s time to look at an important improper integral because it builds the foundation for what we are about to see…. If the improper integral \\(\\int\_{0}^{\\infty} e^{-s x} f(x) d x\\) converges for a value of \\(s=s\_{0}\\), then it converges for every \\(s\>s\_{0}\\). And this integral, if it exists, is a function of \\(\\mathrm{s}\\) and is called the Laplace Transform\! ### Definition of the Laplace Transform By definition, the Laplace transform assumes that \\(f(x)\\) is a function for which the integral exists for some value of \\(s\\), then we say it is denoted as: \\begin{align\*} L\\{f(x)\\}=F(s)=\\int\_{0}^{\\infty} e^{-s x} f(x) d x \\end{align\*} ## Basic Transforms Table Now, computing transforms directly can be a bit complicated and tedious, so it’s by far easier to use a table of transforms to help simplify the process for us. \\begin{equation} \\begin{array}{\|c\|c\|} \\hline \\text { If } f(x)= & \\text { Then } L\\{f(x)\\}=F(s)= \\\\ \\hline 1 & \\frac{1}{s} \\\\ \\hline k & \\frac{k}{s}\>0 \\\\ \\hline e^{a x} & \\frac{1}{s-a} \\\\ \\hline x^n, n=1,2,3, \\ldots & \\frac{n !}{s^{n+1}} \\\\ \\hline x^n e^{a x}, n=1,2,3, \\ldots & \\frac{n !}{(s-a)^{n+1}} s\>a \\\\ \\hline \\sin (a x) & \\frac{a}{s^2+a^2} \\\\ \\hline \\cos (a x) & \\frac{s}{s^2+a^2} \\\\ \\hline \\sinh (a x) & \\frac{a}{s^2-a^2}, s\>\|a\| \\\\ \\hline \\cosh (a x) & \\frac{s}{s^2-a^2}, s\>\|a\| \\\\ \\hline x \\sin (a x) & \\frac{2 a s}{\\left(s^2+a^2\\right)^2} \\\\ \\hline x \\cos (a x) & \\frac{s^2-a^2}{\\left(s^2+a^2\\right)^2} \\\\ \\hline e^{a x} \\sin (b x) & \\frac{b}{(s-a)^2+b^2} \\\\ \\hline e^{a x} \\cos (b x) & \\frac{s-a}{(s-a)^2+b^2} \\\\ \\hline \\end{array} \\end{equation} Keep in mind that this table isn’t exhaustive, but it does provide a solid foundation for harnessing this impressive new tool\! You might be wondering, “What is this, and how does it help solve differential equations?” Great question! Let’s explore a few examples together to better understand its applications. ## Properties of the Laplace Transform But before we do, I want to point out **two critical properties**, as the Laplace transform is *linear* and upholds both *homogeneity* and *superposition*. The Laplace Transform has two essential properties, **linearity** and **superposition**, which make it useful for solving complex problems: - *Linearity (Homogeneity)*: This means that if you multiply a function by a constant, you can just multiply the Laplace Transform of that function by the same constant. - *Superposition*: This means that if you add two functions together, you can simply add their Laplace Transforms separately. These properties make working with the Laplace Transform **easier** and **more efficient**, helping us analyze complex systems and solve differential equations in various fields like engineering, physics, and mathematics. If \\(\\mathrm{a}\\) is a constant and \\(\\mathrm{f}\\) and \\(\\mathrm{g}\\) are functions, then \\begin{equation} \\begin{aligned} & L\\{a f(x)\\}=a L\\{f(x)\\} \\\\ & L\\{f(x) \\pm g(x)\\}=L\\{f(x)\\} \\pm L\\{g(x)\\} \\end{aligned} \\end{equation} ### Example: Laplace Transform of a Polynomial Function Find the Laplace transform of the function \\(f(x)=3 x^{5}\\) First, we will use our first property of linearity and pull out the leading coefficient. \\begin{equation} \\begin{aligned} & L\\left\\{3 x^5\\right\\} \\\\ & 3 L\\left\\{x^5\\right\\} \\end{aligned} \\end{equation} Next, we will notice that our function is a polynomial of the form \\(x^{n}\\) therefore, we can apply its transform as follows. \\begin{equation} \\begin{aligned} & L\\left\\{x^n\\right\\}=\\frac{n !}{s^{n+1}} \\\\ & 3 L\\left\\{x^5\\right\\}=3\\left(\\frac{5 !}{s^{5+1}}\\right)=3\\left(\\frac{5 !}{s^6}\\right)=\\frac{3(120)}{s^6}=\\frac{360}{s^6}, s\>0 \\end{aligned} \\end{equation} Easy, right? ### Example: Laplace Transform w/ Exponential and Trig Functions Find the Laplace transform of the function \\(f(x)=e^{3 x}+\\cos (5 x)\\) First, we will use our second property and separate our two terms. \\begin{equation} \\begin{aligned} & L\\left\\{e^{3 x}+\\cos (5 x)\\right\\} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\} \\end{aligned} \\end{equation} Next, we will use our table to find our transformation for the exponential function and the trigonometric function separately, as follows. \\begin{align\*} \\begin{aligned} & L\\left\\{e^{a x}\\right\\}=\\frac{1}{s-a} \\text { and } L\\{\\cos (a x)\\}=\\frac{s}{s^{2}+a^{2}} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\}=\\frac{1}{s-3}+\\frac{s}{s^{2}+5^{2}} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\}=\\frac{1}{s-3}+\\frac{s}{s^{2}+25}, s\>3 \\end{aligned} \\end{align\*} Nothing to it\! ## Let’s Wrap Up Together, you’ll explore the Laplace Transform by: - Understanding linearity and breaking up each term into separate parts. - Discussing sufficient conditions of existence, such as piecewise continuous functions. - Working through five detailed examples using the Definition of the Laplace Transform, Improper Integrals, and Integration by Parts. - Creating a table of Basic Transforms and applying them to seven more examples. Let’s go\! ## Video Tutorial w/ Full Lesson & Detailed Examples ![laplace transform example](https://calcworkshop.com/wp-content/uploads/laplace-transform-overview-example.jpg) Get access to all the courses and over 450 HD videos with your subscription *Monthly and Yearly Plans Available* [Get My Subscription Now](https://calcworkshop.com/pricing/) Still wondering if CalcWorkshop is right for you? Take a [Tour](https://calcworkshop.com/tour/) and find out how a membership can take the struggle out of learning math. [Calcworkshop](https://calcworkshop.com/) © 2026 Calcworkshop LLC / [Privacy Policy](https://calcworkshop.com/privacy/) / [Terms of Service](https://calcworkshop.com/terms/) - [About](https://calcworkshop.com/about-me/) - [Reviews](https://calcworkshop.com/reviews/) - [Courses](https://calcworkshop.com/courses/) - [Plans & Pricing](https://calcworkshop.com/pricing/)
Readable Markdown
Ever wondered how to **simplify “difficult” ordinary differential equations**? The *Laplace Transform* is like a skilled translator, converting these complex equations into more approachable forms. ![Jenn (B.S., M.Ed.) of Calcworkshop® teaching laplace transforms](https://calcworkshop.com/wp-content/uploads/jenn-calcworkshop-laplace-transforms.jpg) Jenn, Founder Calcworkshop®, 15+ Years Experience (Licensed & Certified Teacher) Used extensively in **engineering**, the Laplace Transform takes a function of a positive real variable (x or t), often represented as “*time*,” and transforms it into a function of a complex variable, commonly called “*frequency*.” Let’s **jump in** and see what the Laplace transform is all about\! ## Understanding Improper Integrals Okay, so to better understand the Laplace transform, we must first understand the improper integral. If \\(f(x)\\) is a continuous function, then the improper integral \\(\\int\_{0}^{\\infty} f(x) d x\\) exists if the integral approaches a finite limit. In other words, if \\(\\int\_{0}^{\\infty} f(x) d x=L\\), where \\(\\mathrm{L}\\) is a finite limit, then \\(\\int\_{0}^{\\infty} f(x) d x\\) converges to the value of L. And if the limit does not exist, then the improper integral diverges. ### Convergence of Improper Integrals Now it’s time to look at an important improper integral because it builds the foundation for what we are about to see…. If the improper integral \\(\\int\_{0}^{\\infty} e^{-s x} f(x) d x\\) converges for a value of \\(s=s\_{0}\\), then it converges for every \\(s\>s\_{0}\\). And this integral, if it exists, is a function of \\(\\mathrm{s}\\) and is called the Laplace Transform\! ### Definition of the Laplace Transform By definition, the Laplace transform assumes that \\(f(x)\\) is a function for which the integral exists for some value of \\(s\\), then we say it is denoted as: \\begin{align\*} L\\{f(x)\\}=F(s)=\\int\_{0}^{\\infty} e^{-s x} f(x) d x \\end{align\*} ## Basic Transforms Table Now, computing transforms directly can be a bit complicated and tedious, so it’s by far easier to use a table of transforms to help simplify the process for us. \\begin{equation} \\begin{array}{\|c\|c\|} \\hline \\text { If } f(x)= & \\text { Then } L\\{f(x)\\}=F(s)= \\\\ \\hline 1 & \\frac{1}{s} \\\\ \\hline k & \\frac{k}{s}\>0 \\\\ \\hline e^{a x} & \\frac{1}{s-a} \\\\ \\hline x^n, n=1,2,3, \\ldots & \\frac{n !}{s^{n+1}} \\\\ \\hline x^n e^{a x}, n=1,2,3, \\ldots & \\frac{n !}{(s-a)^{n+1}} s\>a \\\\ \\hline \\sin (a x) & \\frac{a}{s^2+a^2} \\\\ \\hline \\cos (a x) & \\frac{s}{s^2+a^2} \\\\ \\hline \\sinh (a x) & \\frac{a}{s^2-a^2}, s\>\|a\| \\\\ \\hline \\cosh (a x) & \\frac{s}{s^2-a^2}, s\>\|a\| \\\\ \\hline x \\sin (a x) & \\frac{2 a s}{\\left(s^2+a^2\\right)^2} \\\\ \\hline x \\cos (a x) & \\frac{s^2-a^2}{\\left(s^2+a^2\\right)^2} \\\\ \\hline e^{a x} \\sin (b x) & \\frac{b}{(s-a)^2+b^2} \\\\ \\hline e^{a x} \\cos (b x) & \\frac{s-a}{(s-a)^2+b^2} \\\\ \\hline \\end{array} \\end{equation} Keep in mind that this table isn’t exhaustive, but it does provide a solid foundation for harnessing this impressive new tool\! You might be wondering, “What is this, and how does it help solve differential equations?” Great question! Let’s explore a few examples together to better understand its applications. ## Properties of the Laplace Transform But before we do, I want to point out **two critical properties**, as the Laplace transform is *linear* and upholds both *homogeneity* and *superposition*. The Laplace Transform has two essential properties, **linearity** and **superposition**, which make it useful for solving complex problems: - *Linearity (Homogeneity)*: This means that if you multiply a function by a constant, you can just multiply the Laplace Transform of that function by the same constant. - *Superposition*: This means that if you add two functions together, you can simply add their Laplace Transforms separately. These properties make working with the Laplace Transform **easier** and **more efficient**, helping us analyze complex systems and solve differential equations in various fields like engineering, physics, and mathematics. If \\(\\mathrm{a}\\) is a constant and \\(\\mathrm{f}\\) and \\(\\mathrm{g}\\) are functions, then \\begin{equation} \\begin{aligned} & L\\{a f(x)\\}=a L\\{f(x)\\} \\\\ & L\\{f(x) \\pm g(x)\\}=L\\{f(x)\\} \\pm L\\{g(x)\\} \\end{aligned} \\end{equation} ### Example: Laplace Transform of a Polynomial Function Find the Laplace transform of the function \\(f(x)=3 x^{5}\\) First, we will use our first property of linearity and pull out the leading coefficient. \\begin{equation} \\begin{aligned} & L\\left\\{3 x^5\\right\\} \\\\ & 3 L\\left\\{x^5\\right\\} \\end{aligned} \\end{equation} Next, we will notice that our function is a polynomial of the form \\(x^{n}\\) therefore, we can apply its transform as follows. \\begin{equation} \\begin{aligned} & L\\left\\{x^n\\right\\}=\\frac{n !}{s^{n+1}} \\\\ & 3 L\\left\\{x^5\\right\\}=3\\left(\\frac{5 !}{s^{5+1}}\\right)=3\\left(\\frac{5 !}{s^6}\\right)=\\frac{3(120)}{s^6}=\\frac{360}{s^6}, s\>0 \\end{aligned} \\end{equation} Easy, right? ### Example: Laplace Transform w/ Exponential and Trig Functions Find the Laplace transform of the function \\(f(x)=e^{3 x}+\\cos (5 x)\\) First, we will use our second property and separate our two terms. \\begin{equation} \\begin{aligned} & L\\left\\{e^{3 x}+\\cos (5 x)\\right\\} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\} \\end{aligned} \\end{equation} Next, we will use our table to find our transformation for the exponential function and the trigonometric function separately, as follows. \\begin{align\*} \\begin{aligned} & L\\left\\{e^{a x}\\right\\}=\\frac{1}{s-a} \\text { and } L\\{\\cos (a x)\\}=\\frac{s}{s^{2}+a^{2}} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\}=\\frac{1}{s-3}+\\frac{s}{s^{2}+5^{2}} \\\\ & L\\left\\{e^{3 x}\\right\\}+L\\{\\cos (5 x)\\}=\\frac{1}{s-3}+\\frac{s}{s^{2}+25}, s\>3 \\end{aligned} \\end{align\*} Nothing to it\! ## Let’s Wrap Up Together, you’ll explore the Laplace Transform by: - Understanding linearity and breaking up each term into separate parts. - Discussing sufficient conditions of existence, such as piecewise continuous functions. - Working through five detailed examples using the Definition of the Laplace Transform, Improper Integrals, and Integration by Parts. - Creating a table of Basic Transforms and applying them to seven more examples. Let’s go\! ## Video Tutorial w/ Full Lesson & Detailed Examples ![laplace transform example](https://calcworkshop.com/wp-content/uploads/laplace-transform-overview-example.jpg) Get access to all the courses and over 450 HD videos with your subscription *Monthly and Yearly Plans Available* [Get My Subscription Now](https://calcworkshop.com/pricing/) Still wondering if CalcWorkshop is right for you? Take a [Tour](https://calcworkshop.com/tour/) and find out how a membership can take the struggle out of learning math.
ML Classification
ML Categoriesnull
ML Page Typesnull
ML Intent Typesnull
Content Metadata
Languageen-us
Authornull
Publish Time2023-04-18 15:10:07 (3 years ago)
Original Publish Time2018-10-17 13:12:52 (7 years ago)
RepublishedYes
Word Count (Total)1,197
Word Count (Content)923
Links
External Links4
Internal Links112
Technical SEO
Meta NofollowNo
Meta NoarchiveNo
JS RenderedNo
Redirect Targetnull
Performance
Download Time (ms)23
TTFB (ms)16
Download Size (bytes)11,642
Shard180 (laksa)
Root Hash2704321482360107780
Unparsed URLcom,calcworkshop!/laplace-transform/laplace-transform-overview/ s443