Definite integraton f(x) / sqrt (-x^2-bx-c)

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The discussion focuses on the definite integration of the function f(x) = sin(a x)/x divided by the square root of the negative quadratic Q(x) = x^2 + b x + c. The integration is specifically over the range where Q(x) is negative, which corresponds to the interval between the two real roots of the quadratic. Participants suggest using contour integration techniques and exploring the imaginary part of the expression exp(i a z) / (z sqrt(-(z-q1)(z-q2))) for further analysis.

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ianbell
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I am interested in the definite integration of
f(x) / sqrt(-Q(x))
over the range of x for which quadratic
Q(x) = x^2 + b x + c is negative .

f(x) = sin(a x)/x in particular but others too.

Can anybody point me at any known formulae?

TIA.
 
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This is a case for contour integration!
 
Can you elaborate?

Going complex, we might consider the imaginary part of
exp ( i a z) / ( z sqrt(-(z-q1)(z-q2) )
or more generally f(z) / sqrt(-(z-q1)(z-q2))
as z moves along the real axis from q1 to q2 , the two real roots of quadratic Q(x)=x^2+bx+c.
 

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