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Multiply the

II. Bring down the next two terms for a dividend. Divide it by twice the root just found, and add the quotient, both to the root and to the divisor. divisor thus increased, into the term last root, and subtract the product from the dividend.

placed in the

III. Bring down two or three additional terms and proceed as before.

EXAMPLES.

1. What is the square root of

́a2+2ab+b2+2(a+b)c+c2+2(a+b+c)d+d2?

OPERATION.

ROOT.

(a+b+c+d.

a2+2ab+b2+2(a+b)c+c2+2(a+b+c)d+d2

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4x+12x+5xa—2x3 +7x2-2x+1?

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3. What is the square root of

x1—2x2y2—2x2+y1+2y2+1?

Ans. x2-y2-1.

4. What is the square root of
9x1y*—30x3y3+25x2y2?

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being useless, they have lent their aid in the solution of questions, which required the most refined and delicate analysis.

(103.) Before closing this chapter, we will show the interpretation of the following symbols.

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We know from the nature of multiplication, that O multiplied by a finite quantity, that is, O repeated a finite number of times, must still remain equal to 0; hence, we have this condition

OX A=0.

Dividing both members of (1) by A, we find

A

(1)

(2)

Therefore the symbol will always be equal to 0, as

as long as A is a finite quantity.

(104.) Since the quotient arising from dividing one quantity by another, becomes greater in proportion as the divisor is diminished, it follows that when the divisor becomes less than any assignable quantity, then the quotient will exceed any assignable quantity.

it is usual for mathematicians to say, that

A

0

Hence,

is the re

presentation of an infinite quantity. The symbol employed to represent infinity is ∞, so that we have

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(105.) Dividing both members of (1) by 0, we find

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This being true for all values of A, shows that is

the symbol of an indeterminate quantity.

To illustrate this last symbol, we will take several

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If, before substituting a for x, we divide both numerator and denominator of the given fraction, by x-a, (Art. 42,) we find

x2 -a2 x+a bx-ab

Now, substituting a for x, in this reduced form, we find

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x2-2ax+a2 a2-2a2+a20'

If we reduce this fraction by dividing both numerator and denominator by x-a, we find

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Now, writing a for x in this reduced form, we find

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When a is substituted for x, we have

x3-3x2+3a2x-a3

bx-ab

a3-3a3+3a3—a3

ab-ab

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