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Example 4. Divide 8108 by 26.

8/108÷2√6=4/18=4√2 × √9=3×4√2=12√2.

Example 5. Divide (a2b3d3) by dł.

(a2b2d3)o' ÷ d2 = (a2b2 d3 jo ÷ (d3 }& = (a2 b2 )'3 = (ab)3.

Example 6. Divide (16a3 — 12a2x) by 2a.

First raise 2a to the second power, which=4a2: Then, (16a3 — 12a3x)13 ÷ 4a2 =(4a—3x)13.

INVOLUTION OF RADICAL QUANTITIES.

Example 2. a-√b

a

a2-a√b

-a√b+b

a2-2a√b+b=Square of a- √b.

a-√b

a3-2a3 √b+ab

~a3 √b+2ab-b√b

a3-3a2 √b+3ab-b√b=Cube.

Example 3. 2d+√x

2d+ √x

4d2 +2d√x

+2d√x+x

4d2+4d √x+x=Square of 2d + √г.

2d+√x

8d3 +8d3 √x+2dx

+4d2 √x+4dx+xx

8d3+12d3 √x+6dx+x√x=Cube.

Article 293. b.) √10-√2-3 is here multiplied into ✓10-√2−√3 itself, and the result appears on the next 10+√2+√3) page.

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✓100 * -√4-√6-9-5-2/6 the product of ✓10-√2√3 into 10-2-√3.

5-2/6

5+2√6

25-10√6

25

+106-436

−4√✓/36=25—24=1= the product of.

5-26 into 5+2 √6.

The numerator or denominator of a fraction may be cleared from radical signs without altering the value of the frac tion, if the numerator and denominator be both multiplied by a factor which will render either of them rational. See Day's Algebra, Art. 293, d.

Example 8. The fraction

8

=

4

8x(√3-√2-1) (−√2) 2√+2√2 ̄(√3+√2+1) (√3−√2—1) (— √2) −2√6+2√2. For the first two factors in the denominator, √3+√2+1, and √3−√2-1, when multiplied together-22, which multiplied into the remaining factor, - √2, becomes 4. The factors of the numerator when mul. tiplied together=-8√6+√/8√4+82. Therefore the fraction becomes 8√6+8√4+8√2_−2√+2√4+2√2

4

−2√6+2√4+2√4=4−2√6+2√2.

1

=

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Example 10. a-√b_(a−√b) x (a+√b) _a2 —b

=

a+ √b (a+√b) (a-√b) a2-b

EXAMPLES FOR PRACTICE.

Example 1. Find the 4th root of 81a3. //81a3=3a=3a3a=the 4th root of 81a2.

Example 2. Find the 6th root of (a+b) ̃3.

=1

(a+b)-3=(a+b)-&=3⁄4/(a+1) ̃ ̄3=(a+b)-—6th root

of (a+b)-3.

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Example 3. Find the nth root of (x—y)ś.

(x—y)t×n =(x—y)on = (x-9)=the nth root of (a—b).

Example 4. Find the cube root of -125a3x. -5ax2

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Example 7. Find the square root of x2 -6bx+9b2. x2-6x+963 being the square of a binomial, the square root of it according to Art. 265-x-3b.

Example 8. Find the square root of a +ay+

ya

4

By Art. 265, the square root of a2 +ay+?

y3

2

Example 9. Reduce ax2 to the form of the 6th root.

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Example 10. Reduce -3y to the form of the cube root. (-27y3)= 2/27y3=Answer.

Example 11. Reduce a2 and a3 to a common index. The indices are 2 and, which reduced to a common index and . (a) and a=Answer.

Example 12. Reduce and 5+

to a common index. (44) 11⁄2 and (53) 11⁄2=(256) '1⁄2 and (125)î'1⁄2=Answer.

Example 13. Reduce a1 and to the common index §.

(a) and (b2)=Answer.

Example 14. Reduce 2a and 44 to the common index f. (24) and (42)§=168, and 168=Answer.

Example 15. Remove a factor from √294.

√294=√49× √6=7√6.

Example 16. Remove a factor from √x3-a2x2.

√x2 × √x-a2=x√x—a2.

Example 17. Find the sum and difference of 16a2x

and 4a2x.

√16a2x=√16a2 × √x=4a√x.
√4a2x=√4a2 × √x=2a√x.
4a√x+2a√x=6a✓√x=the sum.
4a√x-2a√x=2a√✓x=the difference.

Example 18. Find the sum and difference of 3/192 and 3/24

/192/64×3/3=43/3.

√24=

8×33/3=23/3.

4 3/3+23/3-6 3/3=sum.

43/3-23/3=23/3=difference.

Example 19. Multiply 73/18 into 53/4. 7/18×53/4=353/72=703/9.

Example 20. Multiply 4+2√2 into 2-√2. 4+2√2×2-2=8-24-8-4=4.

Example 21. Multiply a(a+√c)a into b(a−√e)*. a(a+√c)3×b(a−√e)§=ab(a2—c)§.

Example 22. Multiply 2(a+b) into 3(a+b)". 2(a+b)="×3(a+b)==6(a+b).

n m

Example 23. Divide 654 by 3√2. 6/54÷3√2=2√27=6√3.

Example 24. Divide 43/72 by 23/18.. 43/72÷23/18=23/4.

Example 25. Divide ✓7 by 3/7.

√7÷2/7=√7
3/7

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Example 26. Divide 83/512 by 43/2.
8/512÷4/2=23/256=23/64X3/4-83/4.

Example 27. Find the cube of 1721.
17/21/17/21×17√21=4913/9261

Example 28. Find the square of 5+√2.
(5+√2)X(5+√2)=25+10√2+√4=27+10√2.

Example 29. Find the 4th power of √6.
{√6×{√6צ√6X÷√6=1296√1296=3.

Example 30. Find the cube of √x−√b.
(√x-√b)X(√x−√b)=x−2√bx+b.

(x2√bx+b)x(√x−√b) = x√x − 2√bx2 + b√x -x√b+2√b2x-bb.

Example 31. Find a factor which will make y rational. Vy×V/y2=y; or, y3×3—y.

Example 32. Find a factor which which will make √5— ✓ rational.

(√5−√x)× (√5+√x)=5−x,

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