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9. Required the product of the four following factors, viz.
I.
II.
III.

IV.
(a + b), (a2 + ab + 32), (a - b), and (aạ ab + b2).

Ans. a 86. 10. Required the product of a3 + 3a*x + 3axo + 23 and a _ 3a-x + 3axa 23.

Ans. a 3a*o2 + 3a x4 28. 11. Required the product of a* + aạca + 4 and a - ca.

Ans. Q -- C. 12. Required the product of a + b2 +62 ab

- be and a +b + c.

Ans. 23 3abc + b3 + c3.

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ac

DIVISION.

DIVISION is the converse of mulplication, and is performed like that of numbers; the rule being usually divided into three cases; in each of which like signs give + in the quotient, and unlike signs --, as in finding their products.f

It is here also to be observed, that powers and roots of the same quantity, are divided by subtracting the index of the. divisor from that of the dividend.

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CASE I. When the divisor and dividend are both simple quantities.

RULE.--Set the dividend over the divisor, in the manner of a fraction, and reduce it to its simplest form, by cancelling the letters and figures that are common to each term.

* I would advise the learner to perform the calculation of this example several ways; viz. First, by multiplying the product of the factors I. and II. by the product of the factors III, and IV. Secondly, by multiplying the product of the factors I. and III. by the product of the factors II. and IV. Thirdly, by multiplying the product of the factors I. and IV. by the product of the factors II. and 111. The last method is the most concise. See Euler's Algebra, page 119, Vol. I. --ED. † According to the rule here given for signs, it follows that

ab

+al +0.

-b as will readily appear by multiplying the quotient by the divisor; the signs of the product being then the same as would take place in the former rule.

tab

- ab

aa

a,

torta,

osta,

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a

2a

1 Also - 2a 3a, or

- ; and 9x“ – 3x4

3x1 = 3x5. За 1. Divide 16x® by 8x, and 12a+m2 by - 8ax.

Ans. 2x, and

3x

2

2. Divide - 15aya by 3ay and
15ay by 3ay and - 18axʻy by

18axʻy by — 8ax.

9xy

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3. Divide

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a al.

Ans.

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by d, and axi by

31, and many mors 4. Divide 12a2b2 by -- 3a2b, and — 15ayš by 3ay.

- 46, and 548. 5. Divide – 15aRx by 5ax®, and 21a%e2x

3a, and 3axt. 6. Divide - 1722 dc by – 5ašac, and 24xy by 8 V (xy).

17aac

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When the divisor is a simple quantity, and the dividend a

compound one. RULE.—Divide each term of the dividend by the divisor, as in the former case; setting down such as will not divide in the simplest form they will admit of.

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ab + 32

ato (ab +62) - 2b, or

= a + b 26

2

10ab - 15ax (10ab - 15ax) - 5a, or

26 - 32. 5a

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3a.

ab.

30ax - 48x2 (30ax -- 48x*) = 6x, or

ба. 8x,

6x 1. Let 3.0,3 + 6x2 + 3ax -- 15x be divided by 3x.

Ans. 202 + 2x +05. 2. Let 3abc +- 12abx 9a-6 be divided by 3ab.

Ans. C +40 3. Let 40a3b3 + 60ab- 17ab be divided by

Ans. . 40a2b2° _ 60ab + 17. 4. Let 15a+bc - 12acxa + 5ad" be divided by 5ac.

1222 d2 Ans.

5 5. Let 20ax: + 15ax: + 10ax +-5a be divided by 5a.

Ans. 4003 + 3x2 + 200 + 1. 6. Let 6bcdz + 4bzda 26222 be divided by 2b2.

Ans. 3cd + 2da -- bz. 7. Let 14a - 7ab + 21ax - 28a be divided by 7a.

Ans. 2a b + 330 4 8. Let 20ab +60ab3 12abe divided by 4ab.

Ans. 5 - 1562 + 3ab.

3ab +

CASE III.

When the divisor and dividend are both compound qualities.

RULE.-Set them down in the same manner as in division of numbers, ranging the terms of each of them so, that the higher power of one of the letters may stand before the lower.

Then divide the first term of the dividend by the first term of the divisor, and set the result in the quotient, with its proper sign, or simply by itself, if it be affirmative.

This being done, multiply the whole divisor by the term thus found ; and, having subtracted the result from the dividend, bring down as many terms to the remainder as are requisite for the next operation, which perform as before; and so on, till the work is finished, as in common arithmetic.

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a + a) a + 5a2x+- 5ax" + (a? + 4ax +-**

at a 2x ¢

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NOTE 1. If the divisor be not exactly contained in the dividend, the quantity that remains after the division is finished, must be placed over the divisor, at the end of the quotient, in the form of a fraction; thus,*

2203 a to x) a

ax *

Q3 +238

(

22

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Axo to

2.23

* In the case here given, the operation of division may be considered gives the third term, &c.

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2y 2. The division of quantities may also be sometimes carried on, ad infinitum, like a decimal fraction; in which case a few of the leading terms of the quotient will generally be sufficient to indicate the rest, without its being necessary to continue the operation ; thus,

23
a + x) a .
(1 +

&c.*

a? at a

2

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25

as terminated, when the highest power of the letter, in the first or leading term of the remainder, by which the process is regulated, is less than the power of the first term of the divisor; or when the first term of the divisor is not contained in the first term of the remainder; as the succeeding part of the quotient, after this, instead of being integral, as it ought to be, would necessarily become fractional.

* Now, it is easy to perceive that the next or 6th term of the quotient will be and the seventh term .220

and so on, alternately plus and

a minus; this is called the law of continuation of the series. And the sum of all the terms when infinitely continued is said to be equal to the

2 fraction Thus we say the vulgar fraction

when reduced to ata

g' a decimal, is 22222, &c., infinitely continued. The terms in the quotient are found by dividing the remainder by a, the first term of the divisor; thus, the first remainder- x divided by a, gives the second

a5

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term in the quotient; and the second remainder+

divided by a

a

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