Equation typo in NOAA Manual NOS NGS 5 (Stem, 1990)

Michael Dennis wrote that among the most important NGS and C&GS publications, "Perhaps most significant is NOAA Manual NOS NGS 5 (Stem, 1990), the official defining document of SPCS 83." But it has a previously unreported typo in one of its most important equations as shown below. The fact that there's an error is readily apparent because the argument, x, of tan(x) must be an angle and not an angle times a length, but the correction is not so obvious. I've indicated the correction in red.

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