How do I show that the principal value of $\int_{- \infty}^{\infty}\sin(ax)\sin(bx)/x \,dx$ = 0

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How do I show that the principal value of

$\int_{-\infty}^{\infty}\sin(ax)\sin(bx)/x \,dx$

is equal to zero?

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Note that since $f(x) = \dfrac{\sin(ax)\sin(bx)}x$, we have $f(x)$ to be odd. Hence, we have $f(-x) = -f(x)$. Hence, we have $$G(m,n) = \int_{-m}^{-n} f(x)dx + \int_{n}^{m} f(x)dx = 0$$ Hence, the principal value is zero, i.e., $$\lim_{n \to \infty} \lim_{m \to \infty} G(m,n) = 0$$