1. . f (t), g (t) - -, F (p), G (p), α f (t) + β g (t) (α = cost, β = const)- -, α f (t) + β g (t) α F (p) + β G (p).
. sin t, cos t, : ; . , ; .
2. . f (t) - - f (t) F (p), λ > 0 .
-. .
: , ; , ..
3. . f (t) F (p), e α t f (t) F (p − α),. α - .
-. .
: , ; , ..
4. . f (t) F (p) (.. f (t) η (t) F (p)), f (t − t 0) η (t − t 0) e − t 0 p F (p) t 0 ≥ 0.
-. .
, , . .
.
) : : . , ; (t 0 = 1) , .
) : .
) . : T ≤ t ≤ T + τ T + τ ≤ t ≤ T + 2τ ; t > 2τ , , , , , .
) . , .
. f (t) :
. f (t) : , .
. f (t)- t > 0 , T. f 1(t) , f (t):
. ( ). - f 1(t).
.
{ t } - t. : { t } = t n n ≤ t < n + 1, n - . , f 1(t) = t [ η (t) − η (t − 1)] = t η (t) − (t − 1) η (t − 1) − 1 η (t − 1), , .
5. . f (t) - -, f (t) F (p), - -, .
-. ( , {0 ≤ t < +∞, 0 ≤ τ ≤ t }; , , ) .
6. . - f (t) f ′(t), , f (t) F (p), f ′(t) p F (p) − f (+0).
-. f (+0), f (0), ( ) t = 0.
. - f (t) f ′(t), f ″(t), f ′″(t), f (4)(t), , f (n)(t), , F 1(p), F 2(p), F 3(p), , Fn (p), , , f ′(t) F 1(p) = p F (p) − f (+0). f ″(t) F 2(p) = p F 1(p) − f ′(+0) = p 2 F (p) − p f (+0) − f ′(+0), f ″′(t) F 3(p) = p F 2(p) − f ″(+0) = p 3 F (p) − p 2 f (+0) − p f ′(+0) − f ″(+0), , f (n)(t) Fn (p) = p nF (p) − p n − 1 f (+0) − p n − 2 f ′(+0) − p n − 3 f ″(+0) − − p f (n − 2)(+0) − f (n − 1)(+0).
7. . f (t) - -, f (t) F (p), t = 0. .
-. q = ρ + i η , p = ξ + i η, ξ ≤ ρ = Re q < +∞: .
:
1. .
: ( 20.2.7)
( 20.2.5) .
2. .
. .
8. . f (t) - -, f (t) F (p), − t f (t) F ′(p).
-. . , .
. : , ; , , , ; , , .
: , , .
..
9. . . .
.
. f 1(t) f 2(t) .
f 1 * f 2: . f 1(t) f 2(t) - -, - -, f 1(t) f 2(t) , 1. , , , , , t < e t.
: f (t) * g (t) = g (t) * f (t), , τ τ 1 = t − τ.
, , .. (f 1 * f 2) * f 3 = f 1 * (f 2 * f 3).
( ). .
-. ( )= .
F 1(p) F 2(p).
. ,
1. . , , .
2. . , , .
3. . , .
. pF (p) G (p), F (p) G (p) - f (t) g (t). , ( , 20.2.8, ); , .
,
.
.
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20.3. .
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f (t) | F (p) | f (t) | F (p) | |||
1. | 1 | 9. | e α t sin β t | |||
2. | t n | 10. | e α t cos β t | |||
3. | e α t | 11. | e α t sh β t | |||
4. | e α t t n | 12. | e α t ch β t | |||
5. | sin β t | 13. | t sin β t | |||
6. | cos β t | 14. | t cos β t | |||
7. | sh β t | 15. | t sh β t | |||
8. | ch β t | 16. | t ch β t |