Integral de exp(-a*x^2)*cos(b*x^2) dx
Solución
/ / / ____\\
| | | / 2 ||
| | | / b ||
| |atan| / -- ||
| | | / 2 ||
| ___ | \\/ a /|
|\/ 2 *cos|----------------|*Gamma(1/4)*Gamma(3/4) / / 2 \\
| \ 2 / | | a ||
|------------------------------------------------- for Or|And(2*|arg(b)| = 0, 2*|arg(a)| < pi), And|2*|arg(a)| = pi, 2*|arg(b)| = 0, -- != -1||
| ________ | | 2 ||
| / 2 \ \ b //
| ____ ___ / b
< 4*\/ pi *\/ a * / 1 + --
| 4 / 2
| \/ a
|
| oo
| /
| |
| | 2
| | / 2\ -a*x
| | cos\b*x /*e dx otherwise
| |
| /
\ 0
⎩⎨⎧4πa41+a2b22cos(2atan(a2b2))Γ(41)Γ(43)0∫∞e−ax2cos(bx2)dxfor(2∣arg(b)∣=0∧2∣arg(a)∣<π)∨(2∣arg(a)∣=π∧2∣arg(b)∣=0∧b2a2=−1)otherwise
=
/ / / ____\\
| | | / 2 ||
| | | / b ||
| |atan| / -- ||
| | | / 2 ||
| ___ | \\/ a /|
|\/ 2 *cos|----------------|*Gamma(1/4)*Gamma(3/4) / / 2 \\
| \ 2 / | | a ||
|------------------------------------------------- for Or|And(2*|arg(b)| = 0, 2*|arg(a)| < pi), And|2*|arg(a)| = pi, 2*|arg(b)| = 0, -- != -1||
| ________ | | 2 ||
| / 2 \ \ b //
| ____ ___ / b
< 4*\/ pi *\/ a * / 1 + --
| 4 / 2
| \/ a
|
| oo
| /
| |
| | 2
| | / 2\ -a*x
| | cos\b*x /*e dx otherwise
| |
| /
\ 0
⎩⎨⎧4πa41+a2b22cos(2atan(a2b2))Γ(41)Γ(43)0∫∞e−ax2cos(bx2)dxfor(2∣arg(b)∣=0∧2∣arg(a)∣<π)∨(2∣arg(a)∣=π∧2∣arg(b)∣=0∧b2a2=−1)otherwise
Piecewise((sqrt(2)*cos(atan(sqrt(b^2/a^2))/2)*gamma(1/4)*gamma(3/4)/(4*sqrt(pi)*sqrt(a)*(1 + b^2/a^2)^(1/4)), ((2*Abs(arg(b)) = 0))∧(2*Abs(arg(a)) < pi))∨((Eq(2*Abs(arg(a), pi))∧(2*Abs(arg(b)) = 0)∧(Ne(a^2/b^2, -1)))), (Integral(cos(b*x^2)*exp(-a*x^2), (x, 0, oo)), True))
Estos ejemplos se pueden aplicar para introducción de los límites de integración inferior y superior.