Edexcel Paper 2 2020 October — Question 3

Exam BoardEdexcel
ModulePaper 2 (Paper 2)
Year2020
SessionOctober
TopicLaws of Logarithms

  1. (a) Given that
$$2 \log ( 4 - x ) = \log ( x + 8 )$$ show that $$x ^ { 2 } - 9 x + 8 = 0$$ (b) (i) Write down the roots of the equation $$x ^ { 2 } - 9 x + 8 = 0$$ (ii) State which of the roots in (b)(i) is not a solution of $$2 \log ( 4 - x ) = \log ( x + 8 )$$ giving a reason for your answer.