The Steam Engineer's 

 Handbook 



MATHEMATICS 



SIGNS USED IN CALCULATIONS 



+ Plus, indicates addition; thus, 10+5 is 15. 



Minus, indicates subtraction; thus, 10 5 is 5. 



X Multiplied by, indicates multiplication; thus, 10X5 is 50. 



4- Divided by, indicates division; thus, 10 -f- 5 is 2. 



= Equal to, indicates equality; thus, 12 in. = 1 ft. 



Parentheses, ( ), brackets, [ ], and braces, { },have the same 

 meanings, and signify that the operation indicated within 

 them is to be performed first; or, if more than one pair is used, 

 that indicated within the inner one is to be effected first. 

 Thus, in the expression 5(7 2), the subtraction is to be made 

 first and the difference then multiplied by 5. Again, in the 

 expression %[7 (3 + f)l, the addition indicated within the 

 parentheses is to be performed first, the sum thus found is to 

 be subtracted from 7, and then half of the remainder is to be 

 found. 



The vinculum, , is used for the same purpose as paren- 

 theses, brackets, and braces, but chiefly in connection with the 

 radical sign "V thus, "V . 



The decimal point (.) is placed in a number containing deci- 

 mals, to fix the value of that number; thus, 12.5 is 12 and r^j; 

 1.25 is 1 and ^; and so on. 



An exponent is a figure written above and to the right of a 

 number to indicate the power to which the number is to be 



