Integral trigonométrica

As integrais trigonométricas são uma família de integrais que envolvem funções trigonométricas. Aqui, apresentamos uma lista de tais integrais:

Seno integral[1][2]

S i ( x ) = 0 x sin t t d t , ( | x | < ) {\displaystyle {\rm {Si}}(x)=\int _{0}^{x}{\frac {\sin t}{t}}\,dt,\quad (|x|<\infty )}
s i ( x ) = x sin t t d t = S i ( x ) 1 2 π , ( | x | < ) {\displaystyle {\rm {si}}(x)=-\int _{x}^{\infty }{\frac {\sin t}{t}}\,dt={\rm {Si}}(x)-{\frac {1}{2}}\pi ,\quad (|x|<\infty )}

Cosseno integral:[1][2]

C i ( x ) = θ + ln x + 0 x cos t 1 t d t , ( 0 < x < ) {\displaystyle {\rm {Ci}}(x)=\theta +\ln x+\int _{0}^{x}{\frac {\cos t-1}{t}}\,dt,\quad (0<x<\infty )} , θ 0 , 57722 {\displaystyle \theta \approx 0,57722} é a constante de Euler.
C i n ( x ) = 0 x 1 cos t t d t , ( 0 < x < ) {\displaystyle {\rm {Cin}}(x)=\int _{0}^{x}{\frac {1-\cos t}{t}}\,dt,\quad (0<x<\infty )}
c i ( x ) = x cos t t d t , ( 0 < x < ) {\displaystyle {\rm {ci}}(x)=-\int _{x}^{\infty }{\frac {\cos t}{t}}\,dt,\quad (0<x<\infty )}

Seno hiperbólico integral:[2]

S h i ( x ) = 0 x sinh t t d t {\displaystyle {\rm {Shi}}(x)=\int _{0}^{x}{\frac {\sinh t}{t}}\,dt}

Co-seno hiperbólico integral:[2]

C h i ( x ) = θ + ln x + 0 x cosh t 1 t d t {\displaystyle {\rm {Chi}}(x)=\theta +\ln x+\int _{0}^{x}{\frac {\cosh t-1}{t}}\,dt}
cinh ( x ) = 0 x cosh ( t ) 1 t d t {\displaystyle {\text{cinh}}(x)=\int _{0}^{x}{\frac {\cosh(t)-1}{t}}dt}

Veja também

  • Constante de Euler-Mascheroni
  • Exponencial integral

Referências

  1. a b ABRAMOWITZ, M.; STEGUN, I.A.; Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. National Bureau of Standards, Applied Mathematical Series, 1964. ()
  2. a b c d Bronshtein, I.N.;; et al. (2007). Handbook of Mathematics 5 ed. [S.l.]: Springer. ISBN 9783540721215