Limit at Infinity of Sine Integral Function/Corollary

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Corollary to Limit at Infinity of Sine Integral Function

$\ds \lim_{x \mathop \to -\infty} \map \Si x = -\frac \pi 2$


where $\Si$ denotes the sine integral function.


Proof

\(\ds \map \Si {-x}\) \(=\) \(\ds -\map \Si x\) Sine Integral Function is Odd
\(\ds \lim_{x \mathop \to -\infty} \map \Si x\) \(=\) \(\ds -\lim_{x \mathop \to +\infty} \map \Si x\)
\(\ds \) \(=\) \(\ds -\frac \pi 2\) Limit at Infinity of Sine Integral Function

$\blacksquare$