^64 ALGEBRA. 



one, except it be a single quantity, or the first in n series 

 of quantities, then the sign -j- is frequently omitted : thus 

 tif signifies the same as +j, and the series <r/-f-^ — -<r-}-^ the 

 same as -^a-^b — c-^-d j so that, If any single quantity, ot 

 if the first term in any number of terms, have not a sign 

 before it, then it is always understood to be affirmative. 



4. J^ike sigfts are either al| .positive, or all negati\;e ; but 

 signs are U7ilihy when some are positive and others negative^ 



5. Singlcy or simple^ quantities consist of one term only, 



In multiplying simple quantities, We frequently omit 

 \\i^ sign X, and join the letters ; thus, ah signifies tha 

 Game as ^/X^ ; and ahcy the same as aY^hy^c, And these 

 products, vizi axb, or ab^ and abc, are called single or 

 simple quantities, as v/ell as the factors, viz. a^ b, r, from 

 "w-hich they are produced) and the same is to be observed 

 or the products, arising from .the. multiplication of any 

 number of sim«ple quantities. 



6. If ati algebraical quantity Consist of t^^o terms, it l^ 

 tailed a binomial , as a-^-b \ if of three terms, a trinomialy 

 las a-^h-^^c \ if of four terms, a quadritwrnial, as a'\-h-\^c 

 4*^ ; and if there be more terms, it is called a mnlti^ 

 nomialy ox polymmial ; all which are compound quantities. 



When a compound quantity is to be expressed as multi- 

 Jjlied by a simple one, then we place the sign of multipli- 

 cation between them, and draw a line over the compound 

 quantity only \ but when compound quantities are to be 

 represented as multiplied together, tlien we draw a line 

 over each of them, and connect them with a proper sign. 



Thus, a'\-hy^c denotes that the compound quantity a'\'J> is 

 multiplied by the simple quantity c j so that if a were lO^ 



h 6, and c 4, then would a-^-hYsC be 10+6X4} or 16 in* 

 to 4, which Is 64 J and rt+i^Xc-f-i expresses the product 



