ECZ 2020 · O-Level Paper 2 · Question 7 — Graphs of Functions
Question from ECZ 2020 · O-Level Paper 2 · Question 7
(a) The values of x and y are connected by the equation y = x3 + 4x2 + x - 5 as shown in the table below. x-4-3-2-1012y-911-3-51p
(a(i)) Calculate the value of p.[1]
Verified working — step 1
p is the curve's y-value at x = 2:(a(ii)) Using a scale of 2 cm to represent 1 unit on the x-axis and 2 cm to represent 5 units on the y-axis for -4 ≤ x ≤ 2 and -10 ≤ y ≤ 25, draw the graph of y = x3 + 4x2 + x - 5.[3]
Verified working — step 1
Plot the table's points: (-4, -9), (-3, 1), …(a(iii)) Use your graph to find the solutions of the equations
(a(iii)(a)) x3 + 4x2 + x - 5 = 0,[2]
Verified working — step 1
The solutions of x3 + 4x2 + x - 5 = …(a(iii)(b)) x3 + 4x2 + x - 5 = 2x + 4.[3]
Verified working — step 1
The equation says curve = line, so draw y = 2x + 4 through (0, 4) and (-2, 0).(b) Express 42x - 1 - 13x + 2 as a single fraction in its lowest terms.[3]
Verified working — step 1
Common denominator (2x - 1)(3x + 2):The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.
Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.
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