Date | May 2009 | Marks available | 5 | Reference code | 09M.1.hl.TZ1.3 |
Level | HL only | Paper | 1 | Time zone | TZ1 |
Command term | Find | Question number | 3 | Adapted from | N/A |
Question
Let \(g(x) = {\log _5}\left| {2{{\log }_3}x} \right|\) . Find the product of the zeros of g .
Markscheme
\(g(x) = 0\)
\({\log _5}\left| {2{{\log }_3}x} \right| = 0\) (M1)
\(\left| {2{{\log }_3}x} \right| = 1\) A1
\({\log _3}x = \pm \frac{1}{2}\) (A1)
\(x = {3^{ \pm \frac{1}{2}}}\) A1
so the product of the zeros of g is \({3^{\frac{1}{2}}} \times {3^{ - \frac{1}{2}}} = 1\) A1 N0
[5 marks]
Examiners report
There were many candidates showing difficulties in manipulating logarithms and the absolute value to solve the equation.