4PM1/02R Jun 2020, Question 8: Solving Exponential and Log Equations
Pearson Edexcel International GCSE Further Pure Mathematics 4PM1 · Paper 2R · Calculator · 7 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Solve log base 3 of x minus twice log base x of 3 equals 1, finding the value(s) of x.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Solution · 7 marks
- 1log_x 3 = 1/log₃ x
- 2Let y = log₃ x: y − 2/y = 1
- 3y² − y − 2 = 0
- 4(y − 2)(y + 1) = 0
- 5log₃ x = 2 or −1
- 6x = 9 or x = 1/3
Answerx = 9 or x = 1/3
Stuck on a step? Read the free lesson: Solving Exponential and Log Equations
Practise more solving exponential and log equations questions
Real 4PM1 past-paper questions, marked on your working like the exam, with a worked solution for every part.
Practise free on LemmaraMore past-paper questions on solving exponential and log equations
Also searched as: 4PM1 2R June 2020 · 4PM1/02R · 4pm1 jun20 2r · question 8.
Lemmara is an independent study tool, not affiliated with or endorsed by Pearson Edexcel. The worked solutions are Lemmara’s own.