s er ap eP m e tr .X w w w om .c Scheme of work – Cambridge IGCSE® Mathematics (US) 0444 Unit 2: Algebra (Extended) Recommended prior knowledge All of Core and particularly Unit 2. Only those parts of the learning objectives or notes and exemplars not included in the core units are itemised, so this document should be read alongside the core document. It is also important that Core 1 and 3 and Extended 1 have been completed and understood. Context There are two Core algebra units and this is the first of two extended Algebra units. Once Core units 1, 2 and 3 and the other prior experience for Core 2, are completed this unit can be slotted in at any point. It is probably best taught in parts as it would provide a very lengthy spell of algebra to complete. Section 2.11 is required before Unit 8 Extended. Outline The unit extends the knowledge of Core 2 so be aware that examination questions that relate to aspects of Core 2 may have a greater degree of challenge as they combine with other areas of mathematics. This unit covers inequalities and solving inequalities, fractional exponents, rearranging and evaluating more complex equations and expressions, interpreting algebraic expressions, squaring a binomial, factorizing difference of squares, trinomial and four term expressions into a product of two parenthesis, algebraic fractions, creation and solution of quadratics, solving equations including rationals and radicals and direct and indirect variation. Syllabus ref Learning objectives Suggested teaching activities Learning resources 2.1 Writing, showing, and interpretation of inequalities on the real number line General guidance Students need to understand that a number to the left of another on the number line is smaller regardless of which side of zero they are working. www.bbc.co.uk/schools/ks3bitesize/maths/ algebra/inequalities_simultaneous/revise3. shtml If using number lines a convention is required to distinguish between the inclusive and the exclusive case. The ‘bbc’ website uses solid blobs and arrows but other sources use open and closed blobs. If students give a key this should clarify for any audience. www.counton.org/resources/ks3framework /pdfs/equations.pdf page 131 Students also need to understand when a problem requires only integers and when it requires all real numbers. A number line can blur this distinction leading to misconceptions. v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 1 Syllabus ref Learning objectives Suggested teaching activities Learning resources Teaching activities Practice recoding a few cases on number lines in the preferred style and some problems where the integers that satisfy a set of inequalities are required. 2.2 Create and solve linear inequalities CCSS: A-CED1 A-CED2 A-REI3 Notes and exemplars e.g., Solve 3x + 5 < 7 Solve –7 ≤ 3n – 1 < 5 General guidance Once the balancing method is understood for solving equations then the same steps can be used for inequalities. Students need to understand why the inequality is reversed for division by a negative number Teaching activities Use statements like -3x< 6 and substitute integer values back into the inequality to convince students of the need to change the direction of the inequality. 2.4 CCSS: A-SSE3 Exponents (indices) Notes and exemplars Includes rules of indices with negatives and fractional indices. 3 e.g., simplify 2x 2 X 5x -4 www.counton.org/resources/ks3framework /pdfs/equations.pdf page 131 www.algebra-class.com/solving-wordproblems-in-algebra.html www.algebralab.org/lessons/lesson.aspx?f ile=Algebra_OneVariableSolvingInequalitie s.xml Past Paper 42 June 2011 Q5a (syllabus 0580) Past Paper 23 June 2011 Q10 (syllabus 0580) Past Paper 41 June 2011 Q9 (syllabus 0580) Past Paper 41 June 2011 Q3c (syllabus 0580) www.algebralab.org/lessons/lesson.aspx?f ile=Algebra_ExponentsRules.xml Past Paper 22 June 2011 Q17 (syllabus 0580) General guidance This is the generalization of Core unit 1, and Extended unit 1 (1.7) Students should be able to solve or simplify using the rules of indices and to substitute values in the simplified expressions. Teaching activities Practice writing the statements in radical form as well. v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 2 Syllabus ref Learning objectives Suggested teaching activities Learning resources 2.5 Rearrangement and evaluation of formulae. Notes and exemplars Formula may include indices or cases where the subject appears twice. e.g., make r the subject of • V = 43 Π r 3 http://mash.dept.shef.ac.uk/RearrangingFo rmulae.html CCSS: A-CED4 • p= 2r -s r +s e.g., y = m2 – 4n2 Find the value of y when m = 4.4 and n = 2.8 Past Paper 22 June 2011 Q11 (syllabus 0580) Past Paper 21 June 2011 Q16b (syllabus 0580) Past Paper 21 June 2011 Q8 (syllabus 0580) General guidance Students must understand the rules of ‘Bodmas’ and be able to write the expressions out in words. Where the letter appears on only one side of the equation then writing it in ‘function machines’ (Core unit 2 (2.3)) can help this ordering. Students need a lot of experience to hone this skill. Teaching activities Give them an expression and ask them to find as many different variations as they can using the ‘clouding the picture’ technique from Core unit 2 (2.3) Repeat with an equation at the centre of a spider diagram and ask students to find as many rearranged forms as they can, making all the letters the subject and with different numbers of terms on each side. 2.6 CCSS: A-CED2 A-REI5 A-REI6 2.7 Create and solve simultaneous linear equations in two variables graphically Interpret algebraic expressions The ‘mash’ resource provides links to a lot of examples, a few require a password, but there are enough that don’t to make this a useful bank of resources. Notes and exemplars See functions 3.2 Past Paper 22 June 2011 Q12 (syllabus 0580) General guidance This has already been suggested in the Core units and the time should be used to practice more complex examples, possibly where the equations need rearranging to have them in a form where the unknowns can be reduced to one after substitution Notes and exemplars e.g. interpret P (1 + r )n as the product of P and a factor not depending on P. CCSS: v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 3 Syllabus ref Learning objectives A-SSE1 2.8 Suggested teaching activities Learning resources General guidance This needs to be dealt with alongside the creation of algebra from problems to solve by equations of all forms and not treated in its own write except when expansion is needed. Expansion of parentheses, including the square of a binomial. Simplify expressions It is unfortunate that P is used here and if used by pupils they should understand the difference between the use of P here, in a probability statement and as an indication of a function statement. They will need to look at the context to distinguish. Notes and exemplars e.g. expand (2x – 5)2 = 4x 2 – 20x + 25 Past Paper 42 June 2011 Q5c (syllabus 0580) General guidance Use the grid method but ensure that students keep the sign with the elements of the expression. (2a -3)(-3a + 4) 2a -3 -3a -6a2 9a 4 8a -12 x -6a2 + 9a + 8a -12 2 = -6a +17a -12 2.9 CCSS: A-SSE2 Factorization: difference of squares trinomial four term Notes and exemplars 9x 2 – 16y 2 = (3x – 4y )(3x + 4y ) 6x 2 + 11x – 10 = (3x – 2)(2x + 5) xy – 3x + 2y – 6 = (x + 2)(y – 3) Past Paper 42 June 2011 Q5b,dii (syllabus 0580) Past Paper 41 June 2011 Q3b (syllabus 0580) General guidance This is an area of mathematics that requires a lot of practice if students are to be successful. Difference of two squares should come after some practice to become a rule. For the other cases examining what happens to the coefficients when parentheses are expanded should help understanding. v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 4 Syllabus ref Learning objectives Suggested teaching activities Learning resources Teaching activities Using a grid and trying to work out what could give the key terms will help find the components to test for the brackets. e.g. 2 = -6a +17a -12 find all the possible values and test 2a, -2a, 3a, -3a, a, -a x -6a, 6a ? ? 2.10 Algebraic fractions: simplification, including use of factorization addition or subtraction of fractions with linear denominators multiplication or division and simplification of two fractions -3, -2, -1, -6, -4, -12, 1, 2, 3, 4, 6, 12 -6a2 -12 Practice a number as a quick starter over a period of weeks to give students enough experience to become familiar with the likely components to use. Notes and exemplars 2 4x - 9 3 4 7x 21x ÷ e.g. simplify , - , 8 8x 2 -10x - 3 2x +1 x 4y 2 Past Paper 22 June 2011 Q15 (syllabus 0580) Past Paper 23 June 2011 Q16 (syllabus 0580) General guidance A number of skills must be brought together having been understood and mastered separately for success with this topic Students must be able to: 1. manipulate fractions by the four rules with numbers effectively and understand the generic principle 2. simplifying fractions 3. simplify algebra 4. understand that a fraction line acts as a parentheses 5. factorize or multiply out parentheses Teaching activities Once the topic has been covered practice a number of examples as a quick starter over a period of weeks to give students enough experience to become v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 5 Syllabus ref Learning objectives Suggested teaching activities Learning resources familiar with the likely components to use. 2.11. CCSS: A-SSE3 A-REI3 Create and solve quadratic equations by: inspection factorization using the quadratic formula completing the square Notes and exemplars e.g. x ² = 49 2x ² + 5x – 3 = 0 3x ² – 2x – 7 = 0 Write x ² – 6x + 9 in the form (x – a)2 + b and state the minimum value of the function. Quadratic formula will be given. Past Paper 42 June 2011 Q5b,diii,iv,e (syllabus 0580) Past Paper 43 June 2011 Q3 (syllabus 0580) Past Paper 21 June 2011 Q16a (syllabus 0580) General guidance Once the 2nd and third cases can be factorized, understanding that one or both brackets can be zero, leads easily to a solution. Practicing the methods for completing the square and using the formulae needs practice. Students must distinguish which method to apply to solve the particular case and to find the clues in questions that could guide that choice. 2.12 CCSS: A-CED1 A-REI2 2.13 CCSS: F-BF2 v1 2Y01 Solve simple rational and radical equations in one variable, and discount any extraneous solutions 3. Functions— Extended curriculum Notes / Exemplars Continuation of a sequence of numbers or patterns; recognise patterns in sequences; generalize to simple algebraic Teaching activities Solving a particular equation by factorizing, completing the square and the formula could promote discussion on this. Notes and exemplars e.g. solve x + 2 = 6, x–3 = 27, 2y 4 = 32 General guidance Students should be able to solve simple equations involving exponents with and without calculators and should know when changing the form will help them to do so. Notes and exemplars • www.cimt.plymouth.ac.uk/projects/mepres/ book9/bk9i10/bk9_10i3.html 2 5 10 17 26 General guidance Use the method of second differences to find the nth term Cambridge IGCSE Mathematics (US) 0444 Past Paper 42 June 2011 Q9 (syllabus 0580) 6 Syllabus ref 2.14 Learning objectives Suggested teaching activities Learning resources statements, including determination of the nth term e.g. Past Paper 43 June 2011 Q11 (syllabus 0580) Past Paper 41 June 2011 Q10 (syllabus 0580) Express direct and inverse variation in algebraic terms and use this form of expression to find unknown quantities Teaching activities Set up a number of quadratic sequences in a spreadsheet and ask students to use the above model to find the nth term. Notes and exemplars e.g. y ∝ x, y ∝ x , y ∝ 1/x, y ∝ 1/x 2 General guidance Students must understand proportionality before they can tackle variation. They must also understand how to find the k by substituting coordinates in the equation. v1 2Y01 Cambridge IGCSE Mathematics (US) 0444 www.algebralab.org/lessons/lesson.aspx?f ile=algebra_conics_inverse.xml www.wdeptford.k12.nj.us/high_school/Fish /Honors%20Alg%20worksheets/Direct%20 and%20Inverse%20Variation%20Workshe et.pdf Past Paper 22 June 2011 Q8 (syllabus 0580) Past Paper 41 June 2011 Q3a (syllabus 0580) 7