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LOGARITHMIC AND TRIGONOMETRIC
FIVE PLACES OF DECIMALS
F. L. SEVENOAK, A.M.
ASSISTANT PRINCIPAL OF THE ACADEMIC DEPARTMENT,
THE MACMILLAN COMPANY
All rights reserved
BY THE MACMILLAN COMPANY.
Set up and electrotyped September, 1896. Reprinted February, May, August, October, 1897; August, 1898.
J. S. Cushing & Co. - Berwick & Smith
Norwood Mass. U.S.A.
BRIEF EXPLANATIONS AND RULES
USE OF THESE TABLES
THE logarithm of a number consists in general of two parts, — an integral part, and a decimal. The integral part is called the characteristic, and the decimal part, when it is so written that it is positive, is called the mantissa.
RULE I. The characteristic of the logarithm of a number greater than unity is less by one than the number of digits in its integral part, and is positive.
Thus, the characteristic of the logarithm of 48226 is 4.
RULE II. The characteristic of the logarithm of a decimal fraction is greater by unity than the number of ciphers immediately after the decimal point, and is negative.
Thus, the characteristic of the logarithm of .048226 is 2. We indicate that the characteristic is negative by writing the minus sign above it.
To find the logarithm of a number.
(a) When the number is between 1 and 100.
The logarithm is on page 1.
(b) When the number consists of one or two significant figures.
The mantissa is on page 1.
The characteristic is found by Rule I. or II.
log 8.5 = 0.92942 ;
log .85 1.92942;