Page 13 - LAPLACE TRANSFORM
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1.2 Laplace Transform of a function by using Integration by parts
Integration by Parts is a special method of integration that is often useful when
two functions are multiplied together,
Integration by parts formula:
∫u v dx = u ∫v dx − ∫u' (∫v dx) dx
• u is the function u(x)
• v is the function v(x)
• u' is the derivative of the function u(x)
Example 2
Compute the following function f(t) using Laplace transform.
1. f (t) = 2 t
2
2. f (t) = 5 t
SOLUTION
∞
1. F(S) = ʆ {ƒ(t)} = ∫ ( ). − dt
∞
= ∫ 2 . − dt
0
7