Academic Decathlon™ The premier scholastic competition for high school students. Mathematics BASIC GUIDE United States Academic Decathlon® Toll Free: 866-511-USAD (8723) Direct: 712-366-3700 Fax: 712-366-3701 Email: [email protected] Website: www.usad.org This material may not be reproduced or transmitted, in whole or in part, by any means, including but not limited to print and electronic, without prior written permission from USAD. © 2005 by United States Academic Decathlon. All rights reserved. Table of Contents Introduction . . . . . . . . . . . . 3 Trigonometry. . . . . . . . . . . 33 Algebra . . . . . . . . . . . . . . . . 4 Calculus . . . . . . . . . . . . . . 36 Properties of Real Numbers. . . . . . . . . . . . . . 4 Polynomials . . . . . . . . . . . . . . . . . . . . . . . . 10 Linear Equations . . . . . . . . . . . . . . . . . . . . . 11 Statistics . . . . . . . . . . . . . . 38 Descriptive Statistics . . . . . . . . . . . . . . . . . .38 Quadratic Equations . . . . . . . . . . . . . . . . . . 11 Measures of Central Tendencies. . . . . . . . . . 39 Factoring . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Rational Expressions. . . . . . . . . . . . . . . . . . 15 Linear Inequalities . . . . . . . . . . . . . . . . . . . 17 Inferential Statistics . . . . . . . . . . . . . . . . . . 40 Binomial Experiments. . . . . . . . . . . . . . . . . 41 Linear Equations in Two Variables . . . . . . . . 18 Normal Probability Distributions . . . . . . . . . 42 Parabolas . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Writing Equations of Lines. . . . . . . . . . . . . . 21 Normal as Approximation to Binomial . . . . . 42 Systems of Equations . . . . . . . . . . . . . . . . . 22 Estimates and Sample Sizes . . . . . . . . . . . . 42 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Estimates and Sample Sizes of Proportions . . 43 Complex Numbers . . . . . . . . . . . . . . . . . . . 24 Testing Hypotheses . . . . . . . . . . . . . . . . . . . 43 Geometry. . . . . . . . . . . . . 26 Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Angles . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 General Testing Procedure . . . . . . . . . . . . . . 43 Testing a Claim about a Mean . . . . . . . . . . . 44 Triangles . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Tests of Proportion . . . . . . . . . . . . . . . . . . . 44 Polygons . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Similar Triangles . . . . . . . . . . . . . . . . . . . . . 29 Correlation and Regression . . . . . . . . . . . . . 44 Measures for Polygonal Regions. . . . . . . . . . 30 Polyhedrons . . . . . . . . . . . . . . . . . . . . . . . . 31 2 Bibliography. . . . . . . . . . . 46 Mathematics Basic Guide Introduction ,WLVEHQHILFLDOWRNQRZWKHVWUXFWXUHDQGQDWXUHRIPDWKHPDWLFVZKLOHOHDUQLQJLW)URPDPDWKHPDWLFLDQ¶VSRLQWRIYLHZ PDWKHPDWLFVLVDOOWKDWFDQEHSURYHGIURPVHWWKHRU\6HWWKHRU\FRQVLVWVRIDFROOHFWLRQRID[LRPV±±DVVXPHGSURSHUWLHV±±RI VHWVZKLFKDUHVWDWHGLQDYHU\SUHFLVHODQJXDJHFDOOHGILUVWRUGHUODQJXDJH1RWHYHU\PDWKHPDWLFLDQXVHVWKHVDPHD[LRP V\VWHPEXWRQHRIWKHPRVWZLGHO\XVHGV\VWHPVLVFDOOHGZermello-Fraenkel2ULJLQDOO\WKHJRDORIDQD[LRPV\VWHPIRUVHW WKHRU\ZDVWRVWDWHDVPDOOQXPEHURIDVVXPSWLRQV±±DVVHOIHYLGHQWDVSRVVLEOH±±DERXWVHWVIURPZKLFKDOOIXQGDPHQWDO SURSHUWLHVRIVHWVDQGWKHUHDOQXPEHUVFRXOGEHSURYHQ +RZHYHULQ.XUW*|GHO±VWDUWOHGWKHPDWKHPDWLFDOFRPPXQLW\E\VKRZLQJWKDWQRVXFKD[LRPV\VWHP 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DQG Y UHVSHFWLYHO\ 7KH sample correlation coefficientLV r= ∑ ( X − X )(Y − Y ) ∑( X−X ) ∑( Y −Y ) = n∑ XY − ∑ X ∑ Y n∑ X − (∑ X ) n∑ Y − ( ∑ Y ) 2QHFDQVKRZWKDW r EHORQJVWR>@,I r LVFORVHWRWKHSDLUHGGDWDVDWLVILHVDZHDNOLQHDUUHODWLRQVKLSDQGZKHQ r LV FORVHWRWKHSDLUHGGDWDVDWLVILHVDVWURQJOLQHDUUHODWLRQVKLS$SRVLWLYHFRUUHODWLRQVXJJHVWVy LQFUHDVHVDV x LQFUHDVHVDQG DQHJDWLYHFRUUHODWLRQVXJJHVWVWKDW y GHFUHDVHVDV x LQFUHDVHV,IZHFRQVLGHURXUSUHYLRXVH[DPSOHWKHFRUUHODWLRQ FRHIILFLHQWIRUWKHGLVFDUGHGSDSHUGDWDLVZKLFKLQGLFDWHVPRGHUDWHO\SRVLWLYHOLQHDUFRUUHODWLRQEHWZHHQWKH KRXVHKROGVL]HDQGWKHZHLJKWRIGLVFDUGHGSDSHU7KLVDOVRVXJJHVWVWKDWDVWKHKRXVHKROGVL]HLQFUHDVHVWKHZHLJKWRI GLVFDUGHGSDSHUDOVRLQFUHDVHV $FROOHFWLRQRISDLUHGGDWD x i y i IRU i = n VDWLVILHVDsimple linear regression modelLIWKHUHH[LVW σ α DQG β VXFK WKDWIRUHDFK xi WKH yi LVDQREVHUYDWLRQIURPDN αxi + β σ :KHQWKHDEVROXWHYDOXHRIWKHFRUUHODWLRQFRHIILFLHQWLV FORVHWRWKHQ\L ≈ α xi + β IRU i = n 7KHJUDSKRI y = α + β x LVFDOOHGWKHregression line7KHYDOXHV α DQG β DUH HVWLPDWHGDV a DQG b UHVSHFWLYHO\ZKHUH a = Y − bX DQG b = HVWLPDWHGUHJUHVVLRQOLQHLV y = + x Mathematics Basic Guide n ∑ XY − ∑ X ∑ Y )RUWKHGLVFDUGHGSDSHUGDWDWKH n∑ X − (∑ X ) 45 Bibliography Bellman, Alan, et. al. Algebra: Tools for a Changing World. Needham, MA: Prentice-Hall, 2001. Eves, Howard. An Introduction to the History of Mathematics. Philadelphia: Saunders College, 1990. Hirsch, Christian R., et. al. Geometry, 2nd ed. Glenview, IL: Scott Foresman, 1987. Hornsby, John and Margaret L. Lial. A Graphical Approach to Precalculus, 2nd ed. Reading, MA: Addison Wesley, 1999. Larson, Roland E., Robert P. Hostetler, and Bruce H. Edwards. Precalculus with Limits: A Graphing Approach. Lexington, MA: D.C. Heath, 1995. Lial, Margaret L. and Charles D. Miller. Trigonometry, 2nd ed. Glenview, IL: Scott Foresman, 1983. Mendenhall, William, Richard L. Schaeffer, and Dennis D. Wackerly. Mathematical Statistics with Applications. Boston: Duxbury Press, 1986. Moore, David A. The Basic Practice of Statistics. New York: W.H. Freeman, 1999. Sobel, Max and Norbert Lerner. Precalculus Mathematics, 5th ed. New York: Prentice Hall, 1995. 46 Mathematics Basic Guide
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