Loading [MathJax]/jax/element/mml/optable/Latin1Supplement.js

User interface language: English | Español

Date May 2017 Marks available 2 Reference code 17M.2.SL.TZ1.T_3
Level Standard Level Paper Paper 2 Time zone Time zone 1
Command term Write down Question number T_3 Adapted from N/A

Question

Consider the function f(x)=0.3x3+10x+2x.

Consider a second function, g(x)=2x3.

Calculate f(1).

[2]
a.

Sketch the graph of y=f(x) for 7x4 and 30y30.

[4]
b.

Write down the equation of the vertical asymptote.

[2]
c.

Write down the coordinates of the x-intercept.

[2]
d.

Write down the possible values of x for which x<0 and f(x)>0.

[2]
e.

Find the solution of f(x)=g(x).

[2]
f.

Markscheme

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

0.3(1)3+101+21     (M1)

 

Note:     Award (M1) for correct substitution into function.

 

=10.8     (A1)(G2)

[2 marks]

a.

M17/5/MATSD/SP2/ENG/TZ1/03.b/M     (A1)(A1)(A1)(A1)

 

Note:     Award (A1) for indication of correct window and labelled axes.

Award (A1) for correct shape and position for x<0 (with the local maximum, local minimum and x-intercept in relative approximate location in 3rd quadrant).

Award (A1) for correct shape and position for x>0 (with the local minimum in relative approximate location in 1st quadrant).

Award (A1) for smooth curve with indication of asymptote (graph should not touch y-axis and should not curve away from the y-axis). The asymptote is only assessed in this mark.

 

[4 marks]

b.

x=0     (A2)

 

Note:     Award (A1) for “x=(a constant)” and (A1) for “(a constant)=0”.

The answer must be an equation.

 

[2 marks]

c.

(6.18, 0) (6.17516, 0)     (A1)(A1)

 

Note:     Award (A1) for each correct coordinate. Award (A0)(A1) if parentheses are missing.

 

[2 marks]

d.

4.99<x<2.47 (4.98688<x<2.46635)     (A1)(A1)

 

Note:     Award (A1) for both correct end points, (A1) for strict inequalities used with 2 endpoints.

 

[2 marks]

e.

0.3x3+10x+2x=2x3     (M1)

 

Note:     Award (M1) for equating the expressions for f and g or for the line y=2x3 sketched (positive gradient, negative y-intercept) on their graph from part (a).

 

(x=) 1.34 (1.33650)     (A1)(G2)

 

Note:     Award a maximum of (M1)(A0) or (G1) for coordinate pair seen as final answer.

 

[2 marks]

f.

Examiners report

[N/A]
a.
[N/A]
b.
[N/A]
c.
[N/A]
d.
[N/A]
e.
[N/A]
f.

Syllabus sections

Topic 2—Functions » SL 2.5—Modelling functions
Show 306 related questions
Topic 2—Functions

View options