Mathematics Self-taught: The Lübsen Method for Self-instruction, and Use in the Problems of Practical Life. I. Arithmetic and Algebra

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Gillespie bros., printers, Stamford, Conn., 1897 - Algebra - 333 pages
 

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Page 270 - To Divide One Number by Another, Subtract the logarithm of the divisor from the logarithm of the dividend, and obtain the antilogarithm of the difference.
Page 36 - If the numerator and denominator of each fraction is multiplied (or divided) by the same number, the value of the fraction will not change. This is because a fraction b/b, b being any number, is equal to the multiplicative identity, 1 . Therefore, Hx8.= 88 _5_x!
Page 57 - Multiply as in whole numbers, and point off as many decimal places in the product as there are decimal places in the multiplicand and multiplier, supplying the deficiency, if any, by prefixing ciphers.
Page 257 - The logarithm of the quotient of two positive numbers is found by subtracting the logarithm of the divisor from the logarithm of the dividend. (6) The logarithm of a power of a positive number is found by multiplying the logarithm of the number by the exponent of the power. For, N" = (oT)
Page 205 - To divide powers of the same base, subtract the exponent of the divisor from the exponent of the dividend.
Page 149 - Multiply each sum by its time, and divide the sum of the products by the whole debt ; the quotient is accounted the mean time. EXAMPLES. 1. A. owes B.
Page 58 - Move the decimal point to the left as many places as there are decimal places in the dividend.
Page 45 - Reduce the fractions to a common denominator and divide the numerator of the dividend by the numerator of the divisor.
Page 193 - ... multiplied by the square of the second, plus the cube of the second term. The above rule may be applied to find the cube of a — b, thus (a - 6)8= [e +(- &)]8 = «8 + 3a2(-7>) + 3a(-&)2 + (-6)« = a3 - 3 o'2b + 3 aft2 - ft3.
Page 272 - Those roots, viz. the 5th, 7th, llth, &c., which are not resolvable by the square and cube roots, seldom occur, and, when they do, the work is most easily performed by logarithms ; for, if the logarithm of any number be divided by the index of the root, the quotient will be the logarithm of the root itself. ARITHMETICAL PROGRESSION.

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