# Key to System of practical mathematics. 2 pt. No.xvii

### Contents

 Valuation of Algebraic Expressions 1 Involution and Evolution 16 Quadratic Equations 32 Equations containing Surds 47 Promiscuous Exercises 60 General Exercises in Algebra 77 Logarithmic Arithmetic 1 1 Analytical Trigonometry 12 12
 Promiscuous Exercises 28 28 Mensuration of Surfaces 38 38 and X 54 46 61 61 and III 67 67 73 73 79 79 86 86

### Popular passages

Page 74 - If two triangles have two angles of the one equal to two angles of the other, each to each, and one side equal to one side, viz.
Page 75 - If the vertical angle of a triangle be 'bisected 'by a straight line which also cuts the base, the rectangle contained by the sides of the triangle is equal to the rectangle contained by the segments of the base, together with the square on the straight line which bisects the angle.
Page 9 - Let x measure у by the units in n, then it will measure cy by the units in nc. 2d. If a quantity measure two others, it will measure their sum or difference. Let a be contained...
Page 15 - ... sin(a + b + c). Again (a) represents the coarse ROM, and bands b and c are two controls of the fine-tuned ROMs so that a < 90°, b < 90 • 2~a and c < 90 • 2~(a + 6). This is shown in Fig. 7-7. Sunderland showed that the trigonometric identity can be written as sin(a + b + c) = sin(a + 6) cos c + cos a cos b sin...
Page 10 - The truth of this rule depends upon these two principles ; 1". If one quantity measure another, it will also measure any multiple of that quantity. Let x measure y by the units in n, then it will measure cy by the units in nc.
Page 139 - Arc, on the Sine and Cosine of an Arc in terms of the Arc itself, and a new Theorem for the Elliptic Quadrant.
Page 137 - The differential of the logarithm of a function is equal to the differential of the function, divided by the function itself.
Page 149 - The pyramid may be conceived to be made up of an infinite number of planes parallel to ABC.
Page 81 - ... sum of any number of quantities is equal to the sum of the corresponding functions of each of these quantities, will be called distributive
Page 86 - We thus derive the following method for multiplying two binomials which have a common first term : The first term of the product is the square of the common first terms of the binomials.