GCSE Mathematics Higher Tier ๐ ( ) ๐๐ ๏จ ๐ ( ) ๐ ๐ = √๐๐ ๏จ ๐ ๐ = ๐= ๐ ๐๐ ๐ N8 Look for the biggest square number factor of the number: ๏จ √๐๐ = √๐๐ × ๐ = ๐√๐ Rationalise the denominator N8 Multiply the numerator and denominator by an expression that makes the denominator an integer: ๐ ๐ × √๐ ๐√๐ ๏จ = = ๐ √๐ √๐ × √๐ ๐ ๐ − √๐ × ๐ − √๐ ๐ − √๐ = ๐(๐ − √๐) ๐๐ Standard form N9 Standard form numbers are of the form ๐ × 10๐ , where 1 ≤ ๐ < 10 and ๐ is an integer. Recurring decimals N10 Make a recurring decimal a fraction: ๏จ ๐ = ๐. ๐๐ฬ๐ฬ (two digits are in the recurring pattern, so multiply by 100) ๐๐๐๐ = ๐๐ฬ. ๐ฬ (this is the same as 23.63ฬ6ฬ) ๐๐๐ = ๐๐. ๐๐ฬ๐ฬ − ๐. ๐๐ฬ๐ฬ = ๐๐. ๐ ๐๐. ๐ ๐๐๐ ๐๐ ๐= = = ๐๐ ๐๐๐ ๐๐ Error intervals N15 Find the range of numbers that will round to a given value: ๏จ ๐ = ๐. ๐๐ (2 decimal places) ๐. ๐๐๐ ≤ ๐ < ๐. ๐๐๐ ๏จ ๐ = ๐๐ (2 significant figures) ๐๐. ๐ ≤ ๐ < ๐๐. ๐ Note use of ≤ and <, and that the last significant figure of each is 5. Equations and identities An equation is true for some particular value of ๐ฅ… ๏จ ๐๐ + ๐ = ๐ ๐ข๐ฌ ๐ญ๐ซ๐ฎ๐ ๐ข๐ ๐ = ๐ …but an identity is true for every value of ๐ฅ ๏จ (๐ + ๐)๐ ≡ ๐๐ + ๐๐๐ + ๐๐ (note the use of the symbol ≡) ๐ ๐ ๐๐ = ๐๐๐ ๐๐ A4 ๐2 − ๐ 2 = (๐ + ๐)(๐ − ๐) ๐๐ − ๐๐ = (๐ + ๐)(๐ − ๐) A5 Functions A7 Combining functions: ๐๐(๐ฅ) = ๐(๐(๐ฅ)) ๏จ If ๐(๐) = ๐ + ๐ ๐๐ง๐ ๐(๐) = ๐๐ ๐๐(๐) = ๐๐ + ๐ ๐๐(๐) = (๐ + ๐)๐ A3 A9 Parallel lines: gradients are equal; perpendicular lines: gradients are “negative reciprocals”. ๏จ ๐ = ๐๐ + ๐ and ๐ = ๐๐ − ๐ are parallel to each other; ๐ = ๐๐ + ๐ ๐ and ๐ = − ๐ + ๐ are perpendicular ๐ A13 Starting with the curve ๐ฆ = ๐(๐ฅ): 0 Translate ( ) for ๐ฆ = ๐(๐ฅ) + ๐ ๐ −๐ Translate ( ) for ๐ฆ = ๐(๐ฅ + ๐) 0 Reflect in ๐ฅ axis for ๐ฆ = −๐(๐ฅ) Reflect ๐ฆ axis for ๐ฆ = ๐(−๐ฅ) Velocity - time graph ๐ฆ = ๐ฅ2 ๐ฆ= A11, A18 If a quadratic equation cannot be factorised, use the formula −๐ ± √๐ 2 − 4๐๐ ๐ฅ= 2๐ ๏จ Solve ๐๐๐ + ๐๐ − ๐ = ๐ ๐= or ๐ = −๐−√๐−(−๐๐) ๐×๐ −๐+√๐−(−๐๐) ๐×๐ A15 Gradient = acceleration (you may need to draw a tangent to the curve at a point to find the gradient); Area under curve = distance travelled. ๐ฆ = sin(๐ฅ°) ๐ฆ = cos(๐ฅ°) ๐ฆ = tan(๐ฅ°) Right angled triangles G20 Pythagoras Theorem. Links all three sides. c No angles. 2 2 2 ๐ +๐ =๐ Trigonometry. Links two sides and one angle. SOHโCAHโTOA a sin๐ = opp cos๐ = adj tan๐ = opp = −๐. ๐๐ = ๐. ๐๐ Advanced trigonometry Complete the square to find the turning point of a quadratic graph. ๏จ ๐ = ๐๐ − ๐๐ + ๐ ๐ = (๐ − ๐)๐ − ๐ + ๐ ๐ = (๐ − ๐)๐ − ๐ Turning point is at (3 , −7) Simultaneous equations B A a A19 One linear, one quadratic; ๐ + ๐๐ = ๐๐ ๏จ Solve { ๐ ๐ + ๐๐ = ๐๐ Rearrange the linear, and substitute into the quadratic ๐ = ๐๐ − ๐๐ so (๐๐ − ๐๐)๐ + ๐๐ = ๐๐ Expand and solve the quadratic ๐๐๐ − ๐๐๐ + ๐๐๐ + ๐๐ = ๐๐ ๐๐๐๐ − ๐๐๐ + ๐๐ = ๐ ๐ = ๐ ๐จ๐ซ ๐ = ๐ Finally, substitute into the linear and solve, pairing values… ๐ + ๐ × ๐ = ๐๐ ๐ฌ๐จ (๐ , ๐) = (4 , 2) ๐ + ๐ × ๐ = ๐๐ ๐ฌ๐จ (๐ , ๐) = (−2 , 4) A24, A25 ๐th term of an arithmetic (linear) sequence is ๐๐ + ๐ ๏จ n๐ญ๐ก term of 5,8,11,14,… is 3๐+2 (always increases by 3; first term is ๐ × ๐ + ๐ = ๐.) ๐th term of a quadratic sequence is ๐๐2 + ๐๐ + ๐ ๏จ First three terms of ๐๐ + ๐๐ − ๐ are 3, 9, 17, … Geometric sequence; multiply each term by a constant ratio ๏จ 3, 6, 12, 24, … (ratio is 2) Fibonacci sequence; make the next term by adding the previous two … ๏จ 2, 4, 6, 10, 16, 26, 42, … hyp Sine Rule Use if you are given an angle-side pair ๐ ๐ ๐ = = Missing side: sin๐ด sin๐ต sin๐ถ sin๐ด sin๐ต sin๐ถ = = ๐ ๐ ๐ Missing angle: b C A is opposite a B is opposite b C is opposite c hyp adj Special values of sin, cos, tan Learn (or be able to find without a calculator)… sin0° = 0, cos0° = 1, 1 sin30° = , 2 cos30° = Cosine Rule Use if you can’t use the sine rule sin45° = Missing side: ๐2 = ๐ 2 + ๐ 2 − 2๐๐cos๐ด sin60° = Missing angle: cos๐ด = ๐2 + ๐ 2 − ๐2 2๐๐ 1 √2 , cos45° = tan0° = 0 1 √3 , tan30° = 2 √3 1 √2 1 √3 , cos60° = , 2 2 sin90° = 1, , tan45° = 1 tan60° = √3 cos90° = 0 Circle theorems G10 ๐ ๐ ๐ 2๐ Angle in a semicircle is 90° ๐ Opposite angles in a Alternate cyclic quadrilateral segment total 180° theorem Areas and volumes Circumference of circle = ๐ × ๐ท Area of circle = ๐ × ๐ 2 θ ๐ ×๐×๐ท 360° ๐ × ๐ × ๐2 Area of sector = 360° Arc length = Area of triangle = ๐๐sin๐ถ 2 a Tangent and radius are perpendicular C cone cross section b frustum b 1 Area of trapezium = (๐ + ๐) × โ P8, P9 Multiply for independent events ๏จ P(6 on dice and H on coin) ๐ ๐ ๐ × = ๐ ๐ ๐๐ Add for mutually exclusive events ๏จ P(5 or 6 on dice) ๐ ๐ ๐ + = ๐ ๐ ๐ Apply these rules to tree diagrams. S3 equal areas; equal frequencies Box plots S4 Interquartile range (IQR) = UQ − LQ 2 1 Volume of prism = area of cross section × length Volume of cone = ๐๐ 2 โ 3 Volume of frustum is difference between the volumes of two cones Transformations Reflection • Line of reflection Translation • Vector a h Probability rules Frequency = frequency density multiplied by class width. This means that bars with the same frequency have the same area. G16, G17, G18, G23 1 R10 ๐ฆ is directly proportional to ๐ฅ: ๐ฆ = ๐๐ฅ for a constant ๐ ๏จ ๐ is directly proportional to ๐๐ ; a = 6 when ๐ = 90. Find ๐ if a = 8. ๐ = ๐๐2 ; ๐ = 6 and ๐ = 90 for ๐; ๐๐ = ๐ × ๐๐ ๐ฌ๐จ ๐ = ๐. ๐, ๐ = ๐. ๐๐๐ ๐ = ๐. ๐ × ๐๐ = ๐๐๐ ๐ฆ is inversely proportional to ๐ฅ: ๐ ๐ฆ๐ฅ = ๐ or ๐ฆ = for a constant ๐ ๐ฅ Histograms ๐ Angle at the centre Angles in the is double the angle same segment at the circumference are equal Formula for compound interest ๐ ๐ Total accrued = ๐ (1 + ) 100 ๏จ I invest £600 at 3% compound interest. What is my account worth after 5 years? ๐ ๐ £๐๐๐ × (๐ + ) = £๐๐๐. ๐๐ ๐๐๐ In general… P(A or B) = P(A) + P(B) − P(A and B) P(A and B) = P(A given B) × P(B) ๐ ๐ Percentages: multipliers R9, R16 Percentage increase or decrease; use a multiplier (powers for repetition) ๏จ Initially there were 20 000 fish in a lake. The number decreases by 15% each year. Estimate the number of fish after 6 years. ๐๐ ๐๐๐ × ๐. ๐๐๐ = ๐ ๐๐๐ (2sf) Direct & inverse proportion G21, G22 c A16 ๐ฅ 2 + ๐ฆ 2 = ๐ 2 is a circle with centre (0 ,0) and radius ๐. ๏จ ๐๐ + ๐๐ = ๐๐ has centre (0 , 0) and radius 5. Sequences ๐ฆ = ๐๐ฅ ๐๐ = √๐ × (−๐. ๐๐๐ … ) − ๐ = โฏ Repeat until you know the solution, or you do as many as the question says. θ b Use “2ndF” or “SHIFT” key to find a missing angle adjacent The longest side of any right angled triangle is the hypotenuse; check that your answer is consistent with this. Equation of a circle Equation of straight line ๐ฆ = m๐ฅ + c m is the gradient; c is the ๐ฆ intercept: ๏จ Find the equation of the line that joins (0 , 3) to (2 , 11) Find its gradient… ๐๐ − ๐ ๐ = =๐ ๐−๐ ๐ …and its y intercept… Passes through (0 , 3), so c = 3. Equation is ๐ = ๐๐ + ๐. Transformations of curves ๐ 1 ๐ฆ= ๐ฅ ๐ฅ3 Quadratics The subject of a formula is the term on its own. Rearrange to ๏จ Make ๐ the subject of ๐๐ + ๐๐ = ๐ − ๐๐ ๐๐ + ๐๐ = ๐ − ๐๐ ๐(๐ + ๐) = ๐ − ๐๐ ๐ − ๐๐ ๐= ๐+๐ ๐ = ๐ฆ๐ + ๐ A20 ๐๐ = ๐√๐ × (−๐. ๐) − ๐ = −๐. ๐๐๐ … or ๐๐๐ ๐−๐ The inverse of ๐ is ๐ −1 ๏จ If ๐(๐) = ๐๐ + ๐ then ๐−๐ ๐−๐ (๐) = ๐ ๐ + √๐ ๐ ๐๐๐ ๐๐๐ Rearrange a formula Surds = ๐๐ ๐ ๐ ) = Iteration You will be given the formula to use: ๏จ Solve ๐๐ + ๐๐ + ๐ = ๐ by using the iteration ๐๐+๐ = ๐√๐๐๐ − ๐. Start with ๐๐ = −๐. ๐. Difference of two squares = √๐๐ = 4 ๏จ ๐๐๐๐ A12 • opposite ๏จ ๐−๐ ๏จ( ๐ Standard graphs For any value a: ๐ ๐ฅ × ๐ ๐ฆ = ๐ ๐ฅ+๐ฆ ๐๐ฅ = ๐ ๐ฅ−๐ฆ ๐๐ฆ (๐ ๐ฅ )๐ฆ = ๐ ๐ฅ๐ฆ G7, G8 Rotation • Centre of rotation • Angle of rotation • Clockwise or anticlockwise Enlargement • Centre of enlargement • Scale factor (if −1 < SF < 1 the shape will get smaller). Similar shapes G19 Ratios in similar shapes and solids: • Length/perimeter 1: ๐ ๐: ๐ • Area 1: ๐2 ๐2: ๐2 • Volume 1: ๐3 ๐3: ๐3 maximum Special indices: for any value a: ๐0 = 1 1 ๐−๐ = ๐ ๐ Statistics upper quartile (UQ) N6, N7 A4 Probability median Powers and roots Laws of indices Geometry & measures smallest frequency N5 Ratio, proportion and rates of change minimum lower quartile (LQ) Listing strategies Product rule for counting: ๏จ ๐ × ๐ × ๐ × ๐ = ๐๐ ways to arrange the letters P, I, X and L. Algebra frequency density Number Here is pretty much all the Higher Tier content we could fit onto an A3 sheet of paper, including all the formulae you are required to know for GCSE. An ๏จ points to an illustrative example. The codes refer to the DfE subject content. Pin this to a wall, keep it on your desk, carry it in your bag, make notes on it (sorry, don’t take it into the examination)…