| Date | November 2018 | Marks available | 4 | Reference code | 18N.2.SL.TZ0.T_4 |
| Level | Standard Level | Paper | Paper 2 | Time zone | Time zone 0 |
| Command term | Sketch | Question number | T_4 | Adapted from | N/A |
Question
Consider the function .
Sketch the graph of y = f (x), for −4 ≤ x ≤ 3 and −50 ≤ y ≤ 100.
Use your graphic display calculator to find the equation of the tangent to the graph of y = f (x) at the point (–2, 38.75).
Give your answer in the form y = mx + c.
Sketch the graph of the function g (x) = 10x + 40 on the same axes.
Markscheme
* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.
(A1)(A1)(A1)(A1)
Note: Award (A1) for axis labels and some indication of scale; accept y or f(x).
Use of graph paper is not required. If no scale is given, assume the given window for zero and minimum point.
Award (A1) for smooth curve with correct general shape.
Award (A1) for x-intercept closer to y-axis than to end of sketch.
Award (A1) for correct local minimum with x-coordinate closer to y-axis than end of sketch and y-coordinate less than half way to top of sketch.
Award at most (A1)(A0)(A1)(A1) if the sketch intersects the y-axis or if the sketch curves away from the y-axis as x approaches zero.
[4 marks]
y = −9.25x + 20.3 (y = −9.25x + 20.25) (A1)(A1)
Note: Award (A1) for −9.25x, award (A1) for +20.25, award a maximum of (A0)(A1) if answer is not an equation.
[2 marks]
correct line, y = 10x + 40, seen on sketch (A1)(A1)
Note: Award (A1) for straight line with positive gradient, award (A1) for x-intercept and y-intercept in approximately the correct positions. Award at most (A0)(A1) if ruler not used. If the straight line is drawn on different axes to part (a), award at most (A0)(A1).
[2 marks]
