Date | May 2009 | Marks available | 4 | Reference code | 09M.1.sl.TZ2.4 |
Level | SL only | Paper | 1 | Time zone | TZ2 |
Command term | Find | Question number | 4 | Adapted from | N/A |
Question
Find log232 .
[1]
a.
Given that log2(32x8y) can be written as px+qy , find the value of p and of q.
[4]
b.
Markscheme
5 A1 N1
[1 mark]
a.
METHOD 1
log2(32x8y)=log232x−log28y (A1)
=xlog232−ylog28 (A1)
log28=3 (A1)
p=5 , q=−3 (accept 5x−3y ) A1 N3
METHOD 2
32x8y=(25)x(23)y (A1)
=25x23y (A1)
=25x−3y (A1)
log2(25x−3y)=5x−3y
p=5 , q=−3 (accept 5x−3y ) A1 N3
[4 marks]
b.
Examiners report
Part (a) proved very accessible.
a.
Although many found part (b) accessible as well, a good number of candidates could not complete their way to a final result. Many gave q as a positive value.
b.