### Popular passages

Page 71 - In any triangle the square of any side is equal to the sum of the squares of the other two sides minus twice the product of these two sides and the cosine of their included angle.
Page 70 - Law of Sines - In any triangle, the sides are proportional to the sines of the opposite angles. That is, sin A = sin B...
Page 121 - A cos 6 = cos a cos c + sin a sin c cos B cos c = cos a cos 6 + sin a sin 6 cos C Law of Cosines for Angles cos A = — cos B...
Page 6 - Radian is the angle subtended, at the centre of a circle, by an arc equal in length to the radius...
Page 72 - In every plane triangle, the sum of two sides is to their difference as the tangent of half the sum of the angles opposite those sides is to the tangent of half their difference.
Page 119 - The law of sines states that in any spherical triangle the sines of the sides are proportional to the sines of their opposite angles: sin a _ sin b __ sin c _ sin A sin B sin C...
Page 115 - Rules are : (1) The sine of the middle part equals the product of the tangents of the adjacent parts. (2) The sine of the middle part equals the product of the cosines of the opposite parts.
Page 121 - ... cos a = cos b cos с + sin b sin с cos A ; (2) cos b = cos a cos с + sin a sin с cos в ; ^ A. (3) cos с = cos a cos b + sin a sin b cos C.
Page 109 - On the bank of a river there is a column 200 feet high, supporting a statue 30 feet high ; the statue to an observer on the opposite bank subtends the same angle as a man 6 feet high standing at the base of the column : find the breadth of the river.
Page 3 - O in the direction contrary to that of the hands of a watch.