Lesson Element – 6.05a Functions Task 1 – Order of Operations a) Use the function diagram cards to build the function diagrams that generate each table of input/output values. b) Express the function in algebraic form. INPUT x May 2015 OUTPUT y + 12 +6 ×3 +2 -8 ÷2 ×4 ×2 -4 +3 Input x Output y Input x Output y Input x Output y -4 -10 -4 4 -4 -4 -2 -4 -2 5 -2 4 0 2 0 6 0 12 2 8 2 7 2 20 4 14 4 8 4 28 Input x Output y Input x Output y Input x Output y -4 -2 -4 -13 -4 -20 -2 2 -2 -5 -2 -14 0 6 0 3 0 -8 2 10 2 11 2 -2 4 14 4 19 4 4 Input x Output y Input x Output y Input x Output y -4 1 -4 -6 -4 -16 -2 2 -2 0 -2 -12 0 3 0 6 0 -8 2 4 2 12 2 -4 4 5 4 18 4 0 May 2015 Task 2 – Inverse Functions Card Sort a) Match the functions to their correct table of input/output values. b) Pair the functions to their inverse functions. x -2 -1 0 1 2 y -5 -2.5 0 2.5 5 x -2 -1 0 1 2 y = 5x - 2 y= x -2 -1 0 1 2 x -2 -1 0 1 2 y 0 5 10 15 20 y= x -2 -1 0 1 2 y= May 2015 2x 5 y -12 -7 -2 3 8 x +2 5 y -9 -7 -5 -3 -1 x -2 5 y -0.8 -0.6 -0.4 -0.2 0 x -2 -1 0 1 2 y= y= x -2 -1 0 1 2 x -2 -1 0 1 2 y = 2x + 5 x -2 5 x -2 -1 0 1 2 y = 5x + 2 y -0.8 -0.4 0 0.4 0.8 y 1 3 5 7 9 y -3.5 -3 -2.5 -2 -1.5 x +5 2 y= y 0 0.2 0.4 0.6 0.8 5x 2 x -2 -1 0 1 2 y 1.5 2 2.5 3 3.5 y = 5( x + 2) x -2 -1 0 1 2 y= x -2 -1 0 1 2 y= y -8 -3 2 7 12 x -5 2 y -2.4 -2.2 -2 -1.8 -1.6 x +5 2 x -2 -1 0 1 2 y -14 -12 -10 -8 -6 y = 2x - 5 x -2 -1 0 1 2 y 4 4.5 5 5.5 6 y = 2( x - 5) The following function diagram cards can be used as a tool kit to build the function diagrams: +2 ×2 -2 ÷2 ×5 -5 +5 ÷5 INPUT x OUTPUT y Extension Draw your own function diagrams and their corresponding inverse function diagrams. Write down both the original function and inverse function in algebraic form. May 2015 Task 3 – Composite Functions a) Investigate which combinations of functions A to D will produce the eight tables of input/output values given below – e.g. function ___ followed by function ___ gives table ___. b) Express the composite function in algebraic form. Function A +2 ×3 Function B Square Function C ×2 +3 ×6 +5 Function D May 2015 x 0 1 2 3 4 5 y 4 25 64 121 196 289 x 0 1 2 3 4 5 y 8 17 26 35 44 53 x 0 1 2 3 4 5 y 3 5 11 21 35 53 x 0 1 2 3 4 5 y 13 25 37 49 61 73 x 0 y 7 x 0 y 11 1 2 3 4 5 13 19 25 31 37 1 2 3 4 5 17 23 29 35 41 x 0 1 y 0 1 x 0 1 y 17 35 2 3 16 81 2 3 53 71 4 5 256 625 4 5 89 107 Extension Create two new function diagrams, E and F, and three new tables of input/output values for any combination of functions A to F. Give these additional diagrams and tables to your classmates to investigate. May 2015