Double integral of absolute value of $\frac{\sin(x)}{x}$

definite integralsimproper-integralsintegrationmultiple integralmultivariable-calculus

Can someone help me with the following question:
$$\iint_{R} \left| \frac{\sin(x)}{x} \right| dA$$
where R is the rectangle formed when $x$ goes from 0 to $\infty$ and $y$ goes from 0 to 1?

I don't actually know to begin this one, because the absolute value makes things slightly strange. Wolfram Alpha can't seem to compute it either.

Best Answer

The integral of $$\left|\frac{\sin x}x\right|$$ diverges because you can find an interval of finite length in every half-period of the sine such that the sine exceeds, say $0.5$. Then the integral can be bounded below by a multiple of the harmonic series.