ƒtƒFƒ‹ƒ}[‚̍ŏI’藝‚̏ؖΎ (559Ϊ½)
γ‰Ί‘OŽŸ1-V
’Šo‰πœ •KŽ€Αͺ―Ά°(–{‰Ζ) (‚Χ) Ž©ID Ϊ½žx ‚ ‚ځ[‚ρ

535: 07/30(…)11:29 ID:O8+PnNqB(1/3) AAS
f(t)=t (-ƒΞ<t?ƒΞ)
b_n=η_(-ƒΞ)^ƒΞ?f(t)sin(nt) dt=η_(-ƒΞ)^ƒΞ?tsin(nt) dt
=-η_(-ƒΞ)^ƒΞ??t(cos(nt)/n)^' ? dt

=-[t/n cos(nt)]_(-ƒΞ)^ƒΞ+1/n η_(-ƒΞ)^ƒΞ?cos(nt) dt
=-(ƒΞ/n cos(nƒΞ)-(-ƒΞ)/n cos(-nƒΞ))+1/n [1/n sin(nt)]_(-ƒΞ)^ƒΞ
=-(ƒΞ/n cos(nƒΞ)+ƒΞ/n cos(nƒΞ))=2ƒΞ (-cos(nƒΞ))/n=2ƒΞ (-1)^(n+1)/n
f(t)=2?_(n=1)^‡?(-1)^(n+1)/n sin(nt)
Θ4
536: 07/30(…)11:30 ID:O8+PnNqB(2/3) AAS
η_0^‡?(sin(x))/x dx
έ/έs (e^(-sx) (sin(x))/x)=-xe^(-sx) (sin(x))/x=-e^(-sx) sin(x)

F(s)=η_0^‡??e^(-sx) (sin(x))/x? dx (s?0)

dF(s)/ds=d/ds η_0^‡??e^(-sx) sin?(x)/x? dx
=η_0^‡??έ/ds e^(-sx) sin?(x)/x? dx
=η_0^‡??-xe^(-sx) sin?(x)/x? dx=-η_0^‡??e^(-sx) sin?(x) ? dx
=-η_0^‡??-1/s (e^(-sx) )^' sin(x)? dx
Θ7
537: 07/30(…)11:31 ID:O8+PnNqB(3/3) AAS
dF(s)/ds+1/s^2 dF(s)/ds=-1/s^2
(1+1/s^2 ) dF(s)/ds=((s^2+1)/s^2 ) dF(s)/ds=-1/s^2
dF(s)/ds=-1/(s^2+1)
F(s)=-η?1/(s^2+1) ds s=tan(ƒΖ) ds=1/(?cos?^2 (ƒΖ) ) dƒΖ
-η?1/(s^2+1) ds=-η??1/(?tan?^2 (ƒΖ)+1)?1/(?cos?^2 (ƒΖ) )? dƒΖ=-ƒΖ=-arctan(s)+C

F(s)=-arctan(s)+C
F(s)=η_0^‡??e^(-sx) sin?(x)/x? dx (s?0)
Θ3
γ‰Ί‘OŽŸ1-V‘ŠΦŽΚ”Β——υέžx—π
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