Solving Laplace Transform: 2\int_{0}^{t}f'(u)sin(9(t-u)du +5cos(9t)

Click For Summary
SUMMARY

The discussion focuses on solving the Laplace Transform of the equation 2∫0tf'(u)sin(9(t-u))du + 5cos(9t). The transformation leads to the equation F(s) = 2(9(sF(s) - f(0)) / (s2 + 81) + 5s / (s2 + 81). The challenge arises from the lack of initial conditions for f(0), which is treated as a constant that influences the final solution. Participants emphasize that f(0) will appear in the final answer as a proportional term.

PREREQUISITES
  • Understanding of Laplace Transforms and their properties
  • Knowledge of integral calculus, specifically integration by parts
  • Familiarity with the sine and cosine functions in the context of transforms
  • Basic concepts of differential equations and initial value problems
NEXT STEPS
  • Study the properties of Laplace Transforms, focusing on linearity and initial conditions
  • Learn about integration techniques, particularly integration by parts, for solving transforms
  • Explore the implications of initial conditions in differential equations
  • Investigate the role of constants in Laplace Transforms and their effect on solutions
USEFUL FOR

Students and professionals in mathematics, engineering, and physics who are working with differential equations and Laplace Transforms, particularly those seeking to understand the impact of initial conditions on solutions.

ensten
Messages
5
Reaction score
0

Homework Statement



Find f(t) for:

[itex]2\int_{0}^{t}f'(u)sin(9(t-u)du +5cos(9t), t\geq0[/itex]

The Attempt at a Solution



[itex]F(s)=2\frac{9(sF(s)-f(0))}{s^2+81}+\frac{5s}{s^2+81}[/itex]

At this point i don't know what to do with f(0) since there are no initial conditions.
What do I do with it?
 
Physics news on Phys.org
It's just a constant that'll appear in your final answer. You'll have a term proportional to f(0).
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
6
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 6 ·
Replies
6
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K