THE INDIAN PUBLIC SCHOOL , COIMBATORE Name : 1 MATHEMATICS – Revision Algebra, Functions & Graphs Grade : IX - Solve the simultaneous equations 1 2 x + y = 5, x - 2y = 6 . y= Answer x = 2 The quantity y varies as the cube of (x + 2). y = 32 when x = 0. Find y when x = 1. Answer y = 3 [4] [3] The wavelength, w, of a radio signal is inversely proportional to its frequency, f. When f = 200, w = 1500. (a) Find an equation connecting f and w. Answer (a) [2] Answer (b) f = [1] (b) Find the value of f when w = 600. 4 Pattern 1 Pattern 2 Pattern 3 The first three patterns in a sequence are shown above. (a) Complete the table. Pattern number 1 Number of dots 5 2 3 4 [1] (b) Find a formula for the number of dots, d, in the nth pattern. Answer (b) d= [1] Answer (c) [1] (c) Find the number of dots in the 60th pattern. (d) Find the number of the pattern that has 89 dots. Answer (d) 5 [1] The length, y, of a solid is inversely proportional to the square of its height, x. (a) Write down a general equation for x and y. Show that when x = 5 and y = 4.8 the equation becomes x 2 y = 120 . [2] (b) Find y when x = 2. [1] (c) Find x when y = 10. [2] (d) Find x when y = x. [2] 6 . In triangle ABC, the line BD is perpendicular to AC. AD = (x + 6)cm, DC = (x + 2) cm and the height BD = (x + 1) cm. The area of triangle ABC is 40 cm2 (i) Show that x2 + 5x – 36 = 0 (ii) Solve the equation x2 + 5x – 36 = 0 (iii) Calculate the length of BC 7 8. 9 y 15 0 –3 3 x – 10 f (x) = x 3 - 5x + 3 for - 3 G x G 3 (a) On the diagram, sketch the graph of y = f (x) . [2] (b) Find the coordinates of the local minimum point. ( ...................... , ...................... ) [2] (c) g (x) = 2x - 1 (i) Solve f (x) = g (x) for - 3 G x G 3. ...................... , ...................... , ...................... [3] (ii) Use your answers to part(i) to solve f (x) 2 g (x) . ....................................................................... [2] 10 f (x) = 3x - 2 g (x) = 5x - 1 h (x) = 1 , x !-1 x+1 (i) Find (a) f(3), ................................................. [1] (b) h(f(3)). ................................................. [1] (ii) Find f(g(x)) in its simplest form. ................................................. [2] (iii) Solve f (x) = g (x) . x = ................................................ [2] (iv) Find g -1 (x) . g -1 (x) = ................................................ [2] 11 y 24 –4 0 2 x Find the equation of this quadratic curve. Answer(b) ................................................................ [3] 12 Simplify 1 ^16x 8 y 2h2 . Answer ................................................................. [2] 13 y 12 –6 0 4 x –12 f (x) = (1 - 2x) (x + 3) (a) On the diagram, sketch the graph of y = f (x) for values of x between x =- 6 and x = 4 . [3] (b) Write down the equations of the asymptotes of the graph of y = f (x) . Answer(b) ...................................................................... .............................................................. [2] Answer(c) ............................................................. [2] (c) Find the range of values for y when x H 0 . y (d) 12 –6 0 4 x –12 On this diagram, sketch the graph of y = (e) Solve (1 - 2x) . (x + 3) [2] (1 - 2x) = 6. (x + 3) Answer(e) x = ............................ or x = ...................... [2] 14 Solve the following equations. (a) log x + log 3 = log 12 Answer(a) x = ................................................................ [1] (b) log x = 3 Answer(b) x = ................................................................ [1] (c) 2log x – log 5 = log 20 Answer(c) x = ................................................................ [3] 15 (a) Simplify. 6x - 3y + 2x + y Answer(a) ............................................................. (b) Find the value of 2a + b + 3c when a = 3, b =- 2 and c = 4 . Answer(b) ............................................................. (c) [2] [2] L = 2x + 3y Find the value of x when L = 18.6 and y = 2.8 . Answer(c) x = ............................................................. [2] Answer(d) x = .............................................................. [2] (d) Solve the equation. 5x - 3 = 7 (e) Complete the mapping diagram for (f) f : x " 2x - 1. x f(x) 0 .... 1 1 2 .... 3 .... [2] Solve. 2x + 3 G 4 (x - 2) Answer ................................................................ [3] 16 These are sketches of the graphs of six functions. A 0 C x x y 0 x y 0 F x y 0 D y 0 E B y x y 0 x In the table below are four functions. Write the correct letter in the table to match each function with its graph. Function Graph f (x) = 2x - 3 f (x) = (x - 2) 2 f (x) = 4x - x 3 f (x) = 5 - 2x [4]