Page images
PDF
EPUB
[merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small]

b = 13.561 (ar. co.) 8.86771

c = 14.091 (ar. co.) 8.85106 (ar. co.) 8.85106

(ar.co.) 8.86771

[blocks in formation]

A 26° 30′, ≥ B = 30° 39', ¦ C = 32° 51'

A = 53° 0′, B=61° 18′, C 65° 42'.

[blocks in formation]

In the same way equations (152-154) would furnish a third method, (155-157) a fourth method, and (158) a fifth method.

Given the three sides.

2. Given the three sides of a triangle equal to 17.856, 13.349, and 11.111; to solve the triangle.

[blocks in formation]
[blocks in formation]

in which

is an infinitesimal, into a series arranged

according to powers of x.

[merged small][merged small][ocr errors][merged small][merged small][merged small]

x

i2

1.2

3

1.2.3

+(-1) (-2)+ &c. (160)

But is infinite, and gives, therefore,

i

[merged small][ocr errors][merged small][ocr errors][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]
[blocks in formation]

This quantity e is one of frequent occurrence in analysis, and is celebrated on account of its having been adopted by Napier as the base of his system of logarithms, which were called by him hyperbolic logarithms, but are known as the Naperian logarithms.

The value of e is easily computed, from the consideration that it is the sum of the series (163), the first term of which is unity, and each succeeding term is obtained by dividing the preceding term by the number of the place of this preceding term.

[blocks in formation]

Logarithm of a number which is nearly equal to unity.

The sixth place is neglected, in the sum of the decimals, as being inaccurate.

96. Corollary. The ath power of e is by (164 and 162)

[blocks in formation]

98. Corollary. The logarithm of (166) is

log. (1+i) i log. e,

[ocr errors]

(166)

which gives, by reversing the sign of i,

=

log. (1) i log. e.

(167)

(168)

99. Problem. To develop log. (1-x) into a series of terms arranged according to the powers of x.

Solution. Let the series be denoted, as follows,

log. (1-x)=A+A, x+A2 x2+&c... +4, x"+&c. (169) so that the number below the letter denotes the power of x of which the letter is the coefficient.

First. To find the value of A; let

which reduces (169) to

x=0

log. 1A 0.

(170)

« PreviousContinue »