Plane Trigonometry

Front Cover
Ginn & Company, 1887
 

Selected pages

Other editions - View all

Common terms and phrases

Popular passages

Page 52 - In any triangle, the square of a side opposite an acute angle is equal to the sum of the squares of the other two sides diminished by twice the product of one of those sides and the projection of the other side upon it.
Page 52 - The square of any side of a triangle is equal to the sum of the squares of the other two sides, diminished by twice the product of the sides and the cosine of the included angle.
Page 23 - From the top of a hill the angles of depression of two successive milestones, on a straight level road leading to the hill, are observed to be 5° and 15°. Find the height of the hill.
Page 20 - Geometry that the area of a triangle is equal to one-half the product of the base by the altitude. Therefore, if a and b denote the legs of a right triangle, and F the area...
Page 100 - Assuming the formula for the sine of the sum of two angles in terms of the sines and cosines of the separate angles, find (i.) sin 75° ; (ii.) sin 3 A in terms of sin A.
Page 53 - The bisector of an angle of a triangle divides the opposite side into segments proportional to the adjacent sides.
Page v - If the number is less than 1, make the characteristic of the logarithm negative, and one unit more than the number of zeros between the decimal point and the first significant figure of the given number.
Page 96 - V-- 7. Prove that the sides of any plane triangle are proportional to the sines of the angles opposite to these sides. If 2s = the sum of the three sides (a, b, c) of a triangle, and if A be the angle opposite to the side a, prove that 2 _ 8. Prove that in any plane triangle C* ~~i
Page 95 - The horizontal distance between the two towers being 492 feet, find the height of Appleton Chapel and the distance of the window above the ground. VII. (Cambridge, Eng. 2nd Previous Exam., Dec.
Page iii - The logarithm of a power of a number is found by multiplying the logarithm of the number by the exponent of the power. For, AŤ = (10°)

Bibliographic information