An interesting approach to Logarithms

I’ve just been marking some C4 past papers and one students response to part a of this one caught my eye:

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The young lady in question had shown real resilience when a number of approaches failed, she then got to 4x = xe^×/2 and took natural logarithms of both sides. At first I thought she had stopped there, but I turned over and found this:

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Not the neatest approach, certainly not the fastest way to reach the answer, but valid mathematical reasoning leading to the correct answer. It shows resilience, perseverance and a real understanding of exponentials and logs. I love this answer and think that it shows a really interesting approach to the question. 

This post was cross-posted to Cavmaths here.

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