2011 A-level H2 Mathematics (9740) Paper 1 Question 2 Suggested Solutions

All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.

(i)
f(-1.5) = (-1.5)^2 a + (-1.5) b + c = 4.5

2.25 a -1.5 b + c = 4.5 \rightarrow (1)

f(2.1) = (2.1)^2 a + (2.1) b + c = 3.2

4.41 a + 2.1 b + c = 3.2 \rightarrow (2)

f(3.4) = (3.4)^2 a + (3.4) b + c = 4.1

11.56 a + 3.4b + c = 4.1 \rightarrow (3)

Using the Graphing Calculator, a = 0.215, b = -0.490, c = 3.281

(ii)

f \prime (x) = 2ax + b > 0 for f to be increasing

\therefore, x > 1.14

KS Comments:

Firstly, students must be attentive to leaving the answers to 3 decimal places. For f(x) is an increasing function, we know that implies that f'(x) > 0.

Comments
    pingbacks / trackbacks

    Leave a Reply to 2011 A-level H2 Mathematics (9740) Suggested Solutions | The Culture Cancel reply

    Contact Us

    CONTACT US We would love to hear from you. Contact us, or simply hit our personal page for more contact information

    Not readable? Change text. captcha txt
    0

    Start typing and press Enter to search