56% of students couldn’t correctly solve the log equation given in the VCAA 2014 Paper 1. Can you solve this one?

Solving Log Equations

Every year, Exam 1 has contained an equation to solve involving exponentials or logs.

 

How well have students done in the past?

  • In 2014, 44% of students correctly solved the log equation
  • In 2013, 56% of students correctly solved the log equation

Thus, if you can master your skills for solving log equations, you’ll likely put yourself ahead of about half the state. No bad, hey?

Test your knowledge:

Try your hand at this Log equation. Let me know if you figure it out by writing your answer below.

 

  • Alyssa Pope

    x=4 or x=-2 ?

    • Mathstp

      Hi Alyssa – on the right track! We just can’t have a negative solution bc the log of a negative number is undefined. So the last step is to discount x=-2. This type of question has appeared a couple of times over the years. Check out VCAA Paper 1 2009 Qn 9 if you’d like another one of these to try ๐Ÿ™‚ http://www.vcaa.vic.edu.au/Documents/exams/mathematics/2009mmCAS1-w.pdf