| George Adams - Geometry - 1813 - 576 pages
...BD, and the angle CBD, to find the angle CDB, and the side CD: to find CDB we use this proportion ; as the sum of the two given sides is to their difference, so is the tangent of half the sum of the two unknown angles to the tangent of half their difference; the angle CDB being... | |
| George Adams - Geometry - 1813 - 648 pages
...proportion must begin with an angle ; and when an angle is wanted, it must begin with a side. As the sun, of the two given sides is to their difference ; so is the tangent of half the sum of the two 3. When two sides of a triangle and the included angle are given, to find the... | |
| John Gummere - Surveying - 1814 - 398 pages
...from 180°, and the remain' der will be the sum of the two unknown angles. Then ; • * * * * • * As the sum of the two given sides, „• Is to their difference ; ,. % So is the tangent -of half the sum of the two uuknown angles, To the tangent of half their difference.* This half difference... | |
| Nautical astronomy - 1821 - 708 pages
...from 90°, the remainder is half he sum of the other angles Then say, as the sum of the sides AC, AB is to their difference, so is the tangent of the half sum of the other angles to the tangent of half their difference; which added o and subtracted Ciom the half sum,... | |
| Thomas Holliday - Surveying - 1838 - 404 pages
...Case When two sides and the angle contained between them are given, to find the rest. u2 Rule.—As the sum of the two given sides is to their difference, so is the tangent of half the sum of the unknown angles to the tangent of half their difference: this half difference being... | |
| Joseph Gwilt - Architects - 1842 - 1114 pages
...which will give the half sum of the said unknown angles ; and using the following ratio, we have — As the sum of the two given sides Is to their difference, So is the tangent of half the sum of their opposite angles To the tangent of half the difference of the same angles. Now... | |
| Nathaniel Bowditch - 1846 - 854 pages
...90° ; the remainder is half the sum of the other angles. Then say, As the sum of the sides, AC, AB, is to their difference, so is the tangent of the half sum of the other angles to the Uingentof half their difference ; which added to and subtracted from the half sum,... | |
| Sir Henry Edward Landor Thuillier - Surveying - 1851 - 826 pages
...3rd. Having two sides, and the angle between them, to find the other two angles and the third side. RULE. As the sum of the two given sides, is to their difference, so is, the Tangent of half the sum of the unknown angles, to the Tangent of half their difference. Half the difference thus... | |
| James Elliot - 1851 - 162 pages
...the given angle from 180° : the remainder will be the sum of the two required angles. Then say,— As the sum of the two given sides is to their difference, so is the tangent of half the sum of the two required angles, to the tangent of half their difference. Having found the... | |
| John William Norie - Nautical astronomy - 1852 - 838 pages
...from the nature of the triangle. II. When two Sides and the Angle contained between them are given. As the sum of the two given sides Is to their difference, So is the tangent of half the sum of the unknown angles To the tangent of half their difference : This half difference added... | |
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