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Submitted By zainthebrain97

Words 2327

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Words 2327

Pages 10

2

Answers

Skills check

1 a

Quadratic functions and equations d x 2 − 25 = 0 (x + 5) (x − 5) = 0 x = ±5

3a − 5 = a + 7 2a = 12 a=6 4 x 2 + 1 = 21 4x 2 = 20 x2 = 5 x =± 5 3(n − 4) = 5(n + 2) 3n − 12 = 5n + 10 2n = −22 n = −11 2k(k − 5) 7a(2a2 + 3a − 7) 2 x 2 + 4 xy + 3 x + 6 y 2x ( x + 2 y ) + 3( x + 2 y )

2

e

x 2 + 2x − 48 = 0 x2 + 8x − 6x − 48 = 0

x(x + 8) − 6(x + 8) = 0 (x + 8) (x − 6) = 0 x = −8 or x = 6 f b

b 2 + 6b + 9 = 0 b 2 + 3b + 3b + 9 = 0 b(b + 3) + 3(b + 3) = 0 (b + 3)2 = 0 b = −3

c

2

a b c

a

6x 2 + 5x − 4 = 0 6x 2 + 8x − 3x − 4 = 0 2x(3x + 4) − 1(3x + 4) = 0 (3x + 4)(2x − 1) = 0 x = − 3 or x =

4 1 2

( 2x + 3) ( x + 2 y )

5a 2 − 10a − ab + 2b 5a ( a − 2 ) − b ( a − 2 ) ( 5a − b ) ( a − 2 ) e (n + 1)(n + 3) f (2x − 3)(x + 1) g (m + 6)(m − 6) h (5x + 9y)( 5x − 9y) d b

5c 2 + 6c − 8 = 0 5c 2 + 10c − 4c – 8 = 0 5c (c + 2) − 4 (c + 2) = 0 (c + 2) (5c − 4) = 0 c = −2 or c = 5

4

Exercise 2A

1 a

c

b

c

x 2 − 3x + 2 = 0 x 2 − x − 2x + 2 = 0 x(x − 1) − 2(x − 1) = 0 (x − 1)(x − 2) = 0 x = 1 or x = 2 a 2 + a − 56 = 0 a 2 + 8a − 7a − 56 = 0 a(a + 8) − 7(a + 8) = 0 (a + 8)(a − 7) = 0 a = −8 or a = 7 m 2 − 11m + 30 = 0 m 2 − 5m − 6m + 30 = 0 m(m − 5) − 6(m − 5) = 0 (m − 5) (m − 6) = 0 m = 5 or m = 6

2h 2 − 3h − 5 = 0 2h 2 − 5h + 2h − 5 = 0 h(2h − 5) + 1(2h − 5) = 0 (h + 1) (2h − 5) = 0 h = −1 or h = 2

5

d

4x 2 − 16x − 9 = 0 4x 2 − 18x + 2x – 9 = 0 2x(2x – 9) + 1(2x – 9) = 0 (2x + 1) (2x − 9) = 0 x = − 1 or x =

2 9 2

e

3t 2 + 14t + 8 = 0 3t 2 + 12t + 2t + 8 = 0 3t (t + 4) + 2(t + 4) = 0 (t + 4) (3t + 2) = 0 t = −4 or t = − 3

2

© Oxford University Press 2012: this may be reproduced for class use solely for the purchaser’s institute

Worked solutions: Chapter 2

1

WORKED SOLUTIONS f 6x 2 + x − 12 = 0 6x 2 + 9x − 8x − 12 = 0 3x(2x + 3) − 2(2x +…...

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...IB Economics SL - Internal Assessment [Draft 1] Front Cover EF International Academy New York Candidate Name Candidate number Teacher Title of the article Avaneesh Chotalia T. Barnes Growth Accelerates, but U.S. Has Lots of Ground to Make Up NY Times http://www.nytimes.com/2012/01/28/ business/economy/us-economy-growsat-modest-2-8-percent-rate.html? _r=1&ref=grossdomesticproduct January 27, 2011 January 14, 2012 Source of the article Date the article was published Date the commentary was written Word Count (750 word maximum) Section of the syllabus the article relates to 627 Macroeconomics ! ! Growth Accelerates, but U.S. Has Lots of Ground to Make Up Scott Eells/Bloomberg News A welder at a Alstrom Heat Transfer in New York City. If the economy sustains its speed, it could ease the unemployment crisis. By CATHERINE RAMPELL Published: January 27, 2011 The American economy picked up a little steam last quarter, growing at its fastest pace in a year and a half. Whether it can sustain that momentum is critical to millions of Americans out of work — and perhaps President Obama’s re-election chances. The New York Times The nation’s economic output grew at an annualized rate of 2.8 percent in the fourth quarter, the Commerce Department reported Friday, probably putting to rest last summer’s fears that a second recession was imminent. Other reports this week on manufacturing and consumer sentiment offered similar, if mild,......

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...International Baccalaureate Organization (known as the IB) offers four high-quality and challenging educational programmes for a worldwide community of schools, aiming to create a better, more peaceful world. This publication is one of a range of materials produced to support these programmes. The IB may use a variety of sources in its work and checks information to verify accuracy and authenticity, particularly when using community-based knowledge sources such as Wikipedia. The IB respects the principles of intellectual property and makes strenuous efforts to identify and obtain permission before publication from rights holders of all copyright material used. The IB is grateful for permissions received for material used in this publication and will be pleased to correct any errors or omissions at the earliest opportunity. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior written permission of the IB, or as expressly permitted by law or by the IB’s own rules and policy. See http://www.ibo.org/copyright. IB merchandise and publications can be purchased through the IB store at http://store.ibo.org. Email: sales@ibo.org International Baccalaureate, Baccalauréat International and Bachillerato Internacional are registered trademarks of the International Baccalaureate Organization. 4076 IB mission statement The International Baccalaureate aims...

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...Peterson House, Malthouse Avenue, Cardiff Gate Cardiff, Wales GB CF23 8GL United Kingdom Phone: + 44 29 2054 7777 Fax: + 44 29 2054 7778 Web site: www.ibo.org c International Baccalaureate Organization 2006 The International Baccalaureate Organization (IBO) was established in 1968 and is a non-profit, international educational foundation registered in Switzerland. The IBO is grateful for permission to reproduce and/or translate any copyright material used in this publication. Acknowledgments are included, where appropriate, and, if notified, the IBO will be pleased to rectify any errors or omissions at the earliest opportunity. IBO merchandise and publications in its official and working languages can be purchased through the IB store at http://store.ibo.org. General ordering queries should be directed to the sales and marketing department in Cardiff. Phone: +44 29 2054 7746 Fax: +44 29 2054 7779 E-mail: sales@ibo.org Printed in the United Kingdom by Antony Rowe Ltd, Chippenham, Wiltshire. 5007 CONTENTS INTRODUCTION 1 NATURE OF THE SUBJECT 3 AIMS 6 OBJECTIVES 7 SYLLABUS OUTLINE 8 SYLLABUS DETAILS 9 ASSESSMENT OUTLINE 53 ASSESSMENT DETAILS 55 c International Baccalaureate Organization 2006 1 INTRODUCTION The International Baccalaureate Diploma Programme (DP) is a rigorous pre-university course of studies, leading to examinations, that meets the needs of highly motivated secondary school students between the ages of 16 and 19 years.......

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