WORLD CENTER ON MINOR PLANETS ESTABLISHEDAT CINCINNATI OBSERVATORY

So far as minor planets are concerned, Cincinnati Observatory has be-come the center of the solar system. The International AstronomicalUnion has designated it as the worl(Ts collecting and distributing centerfor observations on asteroids or minor planets.

Astronomers from all parts of the world will send to Cincinnati observa-tions, ephemerides, and new discoveries, which will then be bulletined bywire, cable and mail to all observatories.

Cincinnati Observatory, headed by Dr. Paul Herget, will thus serve thesame function with regard to minor planets as Harvard College Observa-tory, Cambridge, Mass., does in the distribution of general astronomicaldata by means of its famous series of announcement cards and telegrams.

A NEW METHOD FOR EXTRACTION OFALGEBRAICAL SQUARE ROOT

ST. KAIDY TANChip-Bee Senior Middle School, Amay, China

This article on a method for finding the square root of anyalgebraic integral expression will be found useful and interestingto many readers.

First, let us adopt the example and method as shown inChrystSiVs Algebra, I, p. 217:Find the square root of xlo+6x9+13x3+4:x7-lSx6-12^+

14^-12^+9^-2^+1.The process is thus:

1+3 +2-44-1-1

-12 +9 -2 +11+6 +13 + 4 -18 -12 +14I*

(2)+3 6*+13*6*+ 9

2+(6)+2 4 + 4*-18*4*+12 + 4

24-6+(4)-4 - 8 -22 -12*+14*- 8*-24 -16 +16

2+6+4-(8)+1 2+4-2 -12*+9*2* + 6 + 4 - 8 +1

2+6+4-8+(2)-1 -2-6-4+8 -2*+1*- 2*- 6* - 4*+8*-2*+l!(;

We observe that the numbers marked with an asterisk are thesame as the numbers in the same column upright opposite to

745

746SCHOOL SCIENCE AND MATHEMATICS

them, it is unnecessary to write out repeatedly; and the numberson the left side of the vertical line it is required only to write outthose in the parentheses; Hence the above operation may beshortened as follows: ; ’ >

1+34- 2- 4+,1- l . - . , ::". .

2

6

4

-8

2

/+/+13+ 4-18-

/+12+ 4

-/-22y-24-

^

12+14-12+9-;?’+^

16+16

4- 26+ 4- 8+ 1

/-/-/+/-/-/-/-1-/Ans, –(^+3^+2^-4^+^-1).

If the readers are skilful in mental arithmetic, then the proc-ess can be simplified more briefly as follows:

1+3+ 2-4+ 1- 1 . .

2 y+^+13+4-18-12+14-12+9-2^A K ’ ^�ff’01 ’ ^-.^-22

W-^Another Example: Find the square root of 4^4�12rt<3+25A;2�

16a;+9. . ; �

Solution:

2-3+42- 3+ 4

4 ^-^4-25-16+ 9

-6 ^-24+168- 7

or: 4 H^-1^+25-16+9-6 K >^+ 8-7

As we extract the root of the given expression, it remainsSx�7; consequently, we know the radicand is not a perfectsquare.

Kitchen, dishtowel, 20% asbestos and 80% cotton, wipes dishes fasterand drier because asbestos has ability to absorb considerable quantities ofwater rapidly. Also the asbestos, which is a mineral, imparts a polish tochina and glass. ’ ::