INTRODUCTION. 



RUDIMENTS OF THE MATHEMATICS. 



SRCTION I. OF QUANTITY AND NUMBER. 



1. Definition. The letters of the alphabet are em- 

 ployed £it pleasure for denoting any quantities, as algebrai- 

 cal symbols or abbreviations. But, in general, the first 

 letters in order are used to denote known quantities, and 

 the last to denote unknown quantities ; and constant quan- 

 tities are often distinguished from variable quantities in 

 the same manner. 



2. Definition. Quantities are equal when they are 

 of the same magnitude. 



Scholium. The abbreviation a =z 6 implies that a is equal to 6; 

 a>h that a is greater than h ; and a<h that a is less than h, 



3. Definition. Addition is the joining of magnitudes 

 into one sum. 



Scholium. The symbol of addition is an erect cross; a-\-h im- 

 plies the sum of a and ft, and is called a more b. 



4. Definition. Subtraction is the taking as much 

 from one quantity as is equal to another. 



Scholium. Subtraction is denoted by a single line, as a — h, or 

 a less 6, which is the part of a remaiuing, when a part equal to h has 

 been taken from it. 



B 



